Scarcity, Choice, and Cost

All choices mean that one alternative is selected over another. Selecting among alternatives involves three ideas central to economics: scarcity, choice, and opportunity cost.

Opportunity Cost

It is within the context of scarcity that economists define what is perhaps the most important concept in all of economics, the concept of opportunity cost. Opportunity costThe value of the best alternative forgone in making any choice. is the value of the best alternative forgone in making any choice.

The opportunity cost to you of reading the remainder of this chapter will be the value of the best other use to which you could have put your time. If you choose to spend $20 on a potted plant, you have simultaneously chosen to give up the benefits of spending the $20 on pizzas or a paperback book or a night at the movies. If the book is the most valuable of those alternatives, then the opportunity cost of the plant is the value of the enjoyment you otherwise expected to receive from the book.

The concept of opportunity cost must not be confused with the purchase price of an item. Consider the cost of a college or university education. That includes the value of the best alternative use of money spent for tuition, fees, and books. But the most important cost of a college education is the value of the forgone alternative uses of time spent studying and attending class instead of using the time in some other endeavor. Students sacrifice that time in hopes of even greater earnings in the future or because they place a value on the opportunity to learn. Or consider the cost of going to the doctor. Part of that cost is the value of the best alternative use of the money required to see the doctor. But the cost also includes the value of the best alternative use of the time required to see the doctor. The essential thing to see in the concept of opportunity cost is found in the name of the concept. Opportunity cost is the value of the best opportunity forgone in a particular choice. It is not simply the amount spent on that choice.

The concepts of scarcity, choice, and opportunity cost are at the heart of economics. A good is scarce if the choice of one alternative requires that another be given up. The existence of alternative uses forces us to make choices. The opportunity cost of any choice is the value of the best alternative forgone in making it.

Key Takeaways

• Economics is a social science that examines how people choose among the alternatives available to them.
• Scarcity implies that we must give up one alternative in selecting another. A good that is not scarce is a free good.
• The three fundamental economic questions are: What should be produced? How should goods and services be produced? For whom should goods and services be produced?
• Every choice has an opportunity cost and opportunity costs affect the choices people make. The opportunity cost of any choice is the value of the best alternative that had to be forgone in making that choice.

Try It!

Identify the elements of scarcity, choice, and opportunity cost in each of the following:

1. The Environmental Protection Agency is considering an order that a 500-acre area on the outskirts of a large city be preserved in its natural state, because the area is home to a rodent that is considered an endangered species. Developers had planned to build a housing development on the land.
2. The manager of an automobile assembly plant is considering whether to produce cars or sport utility vehicles (SUVs) next month. Assume that the quantities of labor and other materials required would be the same for either type of production.
3. A young man who went to work as a nurses’ aide after graduating from high school leaves his job to go to college, where he will obtain training as a registered nurse.

Case in Point: Canadians Make a Choice

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Canadian Prime Minister Stephen Harper, head of the Conservative Party, had walked a political tightrope for five years as the leader of a minority government in Canada’s parliamentary system. His opponents, upset by policies such as a reduction in corporate tax rates, sought a no-confidence vote in Parliament in 2011. It passed Parliament overwhelmingly, toppling Harper’s government and forcing national elections for a new Parliament.

The political victory was short-lived—the Conservative Party won the May 2011 election easily and emerged as the ruling party in Canada. This allowed Mr. Harper to continue to pursue a policy of deficit and tax reduction.

Canadian voters faced the kinds of choices we have been discussing. Opposition parties—the New Democratic Party (NDP) and the more moderate Liberal Party—sought higher corporate tax rates and less deficit reduction than those advocated by the Conservatives. Under Mr. Harper, the deficit had fallen by one-third in 2010. He promises a surplus budget by 2015, a plan the International Monetary Fund has termed “strong and credible.”

Canada’s unemployment rate in May, 2011 was 7.4 percent compared to a U.S. rate that month of 9.1 percent. GDP growth in Canada was 3.1 percent in 2010; the Bank of Canada projects 4.2 for its growth rate the first quarter of 2011, compared to a U.S. rate for that quarter of 1.8 percent.

Mr. Stephens employed a stimulus package to battle the recession that began in Canada in 2008. He scaled back that effort in 2010 and 2011, producing substantial reductions in the deficit.

Writing on the eve of the election, Wall Street Journal columnist Mary Anastasia O’Grady termed the vote a “referendum on limited government.” Whether or not that characterization was accurate, Canadians clearly made a choice that will result in lower taxes and less spending than the packages offered by the NDP and Liberal Party.

While the issue did not seem to figure prominently in the 2011 campaign, the NDP platform promised to reduce Canada’s greenhouse gas emissions, which have increased with the development of huge oil deposits in Alberta, deposits that have put Canada in third place (behind Venezuela and Saudi Arabia) in the world in terms of oil reserves. Mr. Harper and the Conservatives have promised to proceed with this development as a key factor in Canada’s growth, while the NDP would restrict it sharply. It is a classic case of the problem when choices are made between environmental quality and economic growth.

Sources: Kathleen Harris, “A Vote for the Economy,” Canadian Business, 84(6), May 9, 2011; Nirmala Menon and Paul Vieira, “Canada’s Conservatives Win Majority,” The Wall Street Journal online, May 3, 2011; Paul Vieira, “Canada’s Budget Deficit Shrinks on Strong Growth,” The Wall Street Journal online, April 22, 2011; Mary Anastasia O’Grady, “Canada’s Capitalism Referendum, The Wall Street Journal online, May 2, 2011. The platform of the NDP is available at http://xfer.ndp.ca/2011/2011-Platform/NDP-2011-Platform-En.pdf.

Answers to Try It! Problems

1. The 500-acre area is scarce because it has alternative uses: preservation in its natural state or a site for homes. A choice must be made between these uses. The opportunity cost of preserving the land in its natural state is the forgone value of the land as a housing development. The opportunity cost of using the land as a housing development is the forgone value of preserving the land.
2. The scarce resources are the plant and the labor at the plant. The manager must choose between producing cars and producing SUVs. The opportunity cost of producing cars is the profit that could be earned from producing SUVs; the opportunity cost of producing SUVs is the profit that could be earned from producing cars.
3. The man can devote his time to his current career or to an education; his time is a scarce resource. He must choose between these alternatives. The opportunity cost of continuing as a nurses’ aide is the forgone benefit he expects from training as a registered nurse; the opportunity cost of going to college is the forgone income he could have earned working full-time as a nurses’ aide.

The Economic Way of Thinking

Economists study choices that scarcity requires us to make. This fact is not what distinguishes economics from other social sciences; all social scientists are interested in choices. An anthropologist might study the choices of ancient peoples; a political scientist might study the choices of legislatures; a psychologist might study how people choose a mate; a sociologist might study the factors that have led to a rise in single-parent households. Economists study such questions as well. What is it about the study of choices by economists that makes economics different from these other social sciences?

Three features distinguish the economic approach to choice from the approaches taken in other social sciences:

1. Economists give special emphasis to the role of opportunity costs in their analysis of choices.
2. Economists assume that individuals make choices that seek to maximize the value of some objective, and that they define their objectives in terms of their own self-interest.
3. Individuals maximize by deciding whether to do a little more or a little less of something. Economists argue that individuals pay attention to the consequences of small changes in the levels of the activities they pursue.

The emphasis economists place on opportunity cost, the idea that people make choices that maximize the value of objectives that serve their self-interest, and a focus on the effects of small changes are ideas of great power. They constitute the core of economic thinking. The next three sections examine these ideas in greater detail.

Microeconomics and Macroeconomics

The field of economics is typically divided into two broad realms: microeconomics and macroeconomics. It is important to see the distinctions between these broad areas of study.

MicroeconomicsThe branch of economics that focuses on the choices made by consumers and firms and the impacts those choices have on individual markets. is the branch of economics that focuses on the choices made by individual decision-making units in the economy—typically consumers and firms—and the impacts those choices have on individual markets. MacroeconomicsThe branch of economics that focuses on the impact of choices on the total, or aggregate, level of economic activity. is the branch of economics that focuses on the impact of choices on the total, or aggregate, level of economic activity.

Why do tickets to the best concerts cost so much? How does the threat of global warming affect real estate prices in coastal areas? Why do women end up doing most of the housework? Why do senior citizens get discounts on public transit systems? These questions are generally regarded as microeconomic because they focus on individual units or markets in the economy.

Is the total level of economic activity rising or falling? Is the rate of inflation increasing or decreasing? What is happening to the unemployment rate? These are the questions that deal with aggregates, or totals, in the economy; they are problems of macroeconomics. The question about the level of economic activity, for example, refers to the total value of all goods and services produced in the economy. Inflation is a measure of the rate of change in the average price level for the entire economy; it is a macroeconomic problem. The total levels of employment and unemployment in the economy represent the aggregate of all labor markets; unemployment is also a topic of macroeconomics.

Both microeconomics and macroeconomics give attention to individual markets. But in microeconomics that attention is an end in itself; in macroeconomics it is aimed at explaining the movement of major economic aggregates—the level of total output, the level of employment, and the price level.

We have now examined the characteristics that define the economic way of thinking and the two branches of this way of thinking: microeconomics and macroeconomics. In the next section, we will have a look at what one can do with training in economics.

Putting Economics to Work

Economics is one way of looking at the world. Because the economic way of thinking has proven quite useful, training in economics can be put to work in a wide range of fields. One, of course, is in work as an economist. Undergraduate work in economics can be applied to other careers as well.

Applying Economics to Other Fields

Suppose that you are considering something other than a career in economics. Would choosing to study economics help you?

The evidence suggests it may. Suppose, for example, that you are considering law school. The study of law requires keen analytical skills; studying economics sharpens such skills. Economists have traditionally argued that undergraduate work in economics serves as excellent preparation for law school. Economist Michael Nieswiadomy of the University of North Texas collected data on Law School Admittance Test (LSAT) scores for the 12 undergraduate majors listed most often by students hoping to enter law school in the class of 2008–9. Table 1.1 "LSAT Scores for Students Taking the Exam in 2008" gives the scores, as well as the ranking for each of these majors in 2008. Economics majors tied philosophy majors for the highest average score.

Table 1.1 LSAT Scores for Students Taking the Exam in 2008

Rank	Major	Average LSAT Score	# of Students
1	Economics	157.4	3,047
1	Philosophy	157.4	2,184
3	Engineering	156.2	2,197
4	History	155.9	4,166
5	English	154.7	5,120
6	Finance	153.4	2,267
7	Political science	153.0	14,964
8	Psychology	152.5	4,355
9	Sociology	150.7	1,902
10	Communications	150.5	2,230
11	Business administration	149.1	1,971
12	Criminal justice	145.5	3,306

Here are the average LSAT scores and rankings for the 12 undergraduate majors with more than 1,900 students taking the test to enter law school in the 2008–2009 academic year.

Source: Michael Nieswiadomy, “LSAT Scores of Economics Majors: The 2008–09 Class Update” Journal of Economic Education, 41:3 (Summer 2010): 331–333.

Did the strong performance by economics and philosophy majors mean that training in those fields sharpens analytical skills tested in the LSAT, or that students with good analytical skills are more likely to major in them? Both were probably at work. Economics and philosophy clearly attract students with good analytical skills—and studying economics or philosophy helps to develop those skills.

Of course, you may not be interested in going to law school. One consideration relevant to selecting a major is potential earnings in that field. The National Association of Colleges and Employers conducts a quarterly survey of salary offers received by college graduates with various majors. The results for the summer 2011 survey for selected majors are given in Table 1.2 "Average Yearly Salary Offers, Summer 2011". If you are going for the big bucks, the best strategy is to major in petroleum engineering. But as the table suggests, economics majors as a group did quite well in 2011.

Table 1.2 Average Yearly Salary Offers, Summer 2011

Major	Average Offer
Petroleum engineering	$80,849
Chemical engineering	65,617
Computer engineering	64,499
Computer science	63,402
Electrical engineering	61,021
Engineering	60,465
Mechanical engineering	60,345
Information science	57,499
Economics	53,906
Finance	52,351
Accounting	49,671
Business administration	44,825
History	40,051
English	39,611
Psychology	34,000

Source: National Association of Colleges and Employers, Average Salary Offer to College Class of 2011 Rises 4.8 Percent, press release at http://www.naceweb.org/Press/Releases/Average_Salary_Offer_to_College_Class_of_2011_Rises_4_8_Percent.aspx. For psychology, median salary offer is reported.

One’s choice of a major is not likely to be based solely on considerations of potential earnings or the prospect of landing a spot in law school. You will also consider your interests and abilities in making a decision about whether to pursue further study in economics. And, of course, you will consider the expected benefits of alternative courses of study. What is your opportunity cost of pursuing a study of economics? Does studying more economics serve your interests and will doing so maximize your satisfaction level? These considerations may be on your mind as you begin to study economics at the college level and obviously students will make many different choices. But, should you decide to pursue a major in economics, you should know that a background in this field is likely to serve you well.

Key Takeaways

• Economists focus on the opportunity costs of choices, they assume that individuals make choices in a way that maximizes the value of an objective defined in terms of their own self-interest, and they assume that individuals make those choices at the margin.
• Economics is divided into two broad areas: microeconomics and macroeconomics.
• A wide range of career opportunities is open to economics majors. Empirical evidence suggests that students who enter the job market with a major in economics tend to earn more than do students in many other majors. Further, economics majors do particularly well on the LSAT.

Try It!

The Department of Agriculture estimated that the expenditures a middle-income, husband–wife family of three would incur to raise one additional child from birth in 2005 to age 17 would be $250,530. In what way does this estimate illustrate the economic way of thinking? Would the Department’s estimate be an example of microeconomic or of macroeconomic analysis? Why?

Case in Point: Opportunity Cost with The Simpsons

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In the animated television comedy The Simpsons, Homer’s father, Grampa Simpson, faced a classic problem in the allocation of a scarce resource—his time. He wanted to spend the day with his girlfriend, Bea—it was, after all, her birthday. His alternative was to spend the day with Homer and the family, which he did not really want to do, partly because they never visited him anyway.

Homer and his family prevailed, however, and insisted on taking Grampa to “Discount Lion Safari,” a local amusement park. The cost of Grampa’s day with his family is the enjoyment he anticipated from spending time with Bea. It all ends up badly for Grampa anyway—Homer’s car breaks down on the way to the park. As for the forgone alternative, Bea dies that day, possibly because of a broken heart from not being able to spend the day with Grampa.

Sources: R. Andrew Luccasen and M. Kathleen Thomas, “Simpsonomics: Teaching Economics Using Episodes of The Simpsons,” The Journal of Economic Education, 41(2), Spring 2010, 136–149. The Simpsons, Episode no. 30, first broadcast 28 March 1991 by Fox, directed by David Silverman and written by Jay Kogen and Wallace Wolodarsky.

Answer to Try It! Problem

The information given suggests one element of the economic way of thinking: assessing the choice at the margin. The estimate reflects the cost of one more child for a family that already has one. It is not clear from the information given how close the estimate of cost comes to the economic concept of opportunity cost. The Department of Agriculture’s estimate included such costs as housing, food, transportation, clothing, health care, child care, and education. An economist would add the value of the best alternative use of the additional time that will be required for the child. If the couple is looking far ahead, it may want to consider the opportunity cost of sending a child to college. And, if it is looking very far ahead, it may want to consider the fact that nearly half of all parents over the age of 50 support at least one child over the age of 21. This is a problem in microeconomic analysis, because it focuses on the choices of individual households.

Models in Economics

All scientific thought involves simplifications of reality. The real world is far too complex for the human mind—or the most powerful computer—to consider. Scientists use models instead. A modelA set of simplifying assumptions about some aspect of the real world. is a set of simplifying assumptions about some aspect of the real world. Models are always based on assumed conditions that are simpler than those of the real world, assumptions that are necessarily false. A model of the real world cannot be the real world.

We will encounter an economic model in Chapter 2 "Confronting Scarcity: Choices in Production". For that model, we will assume that an economy can produce only two goods. Then we will explore the model of demand and supply. One of the assumptions we will make there is that all the goods produced by firms in a particular market are identical. Of course, real economies and real markets are not that simple. Reality is never as simple as a model; one point of a model is to simplify the world to improve our understanding of it.

Economists often use graphs to represent economic models. The appendix to this chapter provides a quick, refresher course, if you think you need one, on understanding, building, and using graphs.

Models in economics also help us to generate hypotheses about the real world. In the next section, we will examine some of the problems we encounter in testing those hypotheses.

Testing Hypotheses in Economics

Here is a hypothesis suggested by the model of demand and supply: an increase in the price of gasoline will reduce the quantity of gasoline consumers demand. How might we test such a hypothesis?

Economists try to test hypotheses such as this one by observing actual behavior and using empirical (that is, real-world) data. The average retail price of gasoline in the United States rose from an average of $2.12 per gallon on May 22, 2005 to $2.88 per gallon on May 22, 2006. The number of gallons of gasoline consumed by U.S. motorists rose 0.3% during that period.

The small increase in the quantity of gasoline consumed by motorists as its price rose is inconsistent with the hypothesis that an increased price will lead to a reduction in the quantity demanded. Does that mean that we should dismiss the original hypothesis? On the contrary, we must be cautious in assessing this evidence. Several problems exist in interpreting any set of economic data. One problem is that several things may be changing at once; another is that the initial event may be unrelated to the event that follows. The next two sections examine these problems in detail.

Normative and Positive Statements

Two kinds of assertions in economics can be subjected to testing. We have already examined one, the hypothesis. Another testable assertion is a statement of fact, such as “It is raining outside” or “Microsoft is the largest producer of operating systems for personal computers in the world.” Like hypotheses, such assertions can be demonstrated to be false. Unlike hypotheses, they can also be shown to be correct. A statement of fact or a hypothesis is a positive statementA statement of fact or a hypothesis..

Although people often disagree about positive statements, such disagreements can ultimately be resolved through investigation. There is another category of assertions, however, for which investigation can never resolve differences. A normative statementA statement that makes a value judgment. is one that makes a value judgment. Such a judgment is the opinion of the speaker; no one can “prove” that the statement is or is not correct. Here are some examples of normative statements in economics: “We ought to do more to help the poor.” “People in the United States should save more.” “Corporate profits are too high.” The statements are based on the values of the person who makes them. They cannot be proven false.

Because people have different values, normative statements often provoke disagreement. An economist whose values lead him or her to conclude that we should provide more help for the poor will disagree with one whose values lead to a conclusion that we should not. Because no test exists for these values, these two economists will continue to disagree, unless one persuades the other to adopt a different set of values. Many of the disagreements among economists are based on such differences in values and therefore are unlikely to be resolved.

Key Takeaways

• Economists try to employ the scientific method in their research.
• Scientists cannot prove a hypothesis to be true; they can only fail to prove it false.
• Economists, like other social scientists and scientists, use models to assist them in their analyses.
• Two problems inherent in tests of hypotheses in economics are the all-other-things-unchanged problem and the fallacy of false cause.
• Positive statements are factual and can be tested. Normative statements are value judgments that cannot be tested. Many of the disagreements among economists stem from differences in values.

Try It!

Look again at the data in Table 1.1 "LSAT Scores for Students Taking the Exam in 2008". Now consider the hypothesis: “Majoring in economics will result in a higher LSAT score.” Are the data given consistent with this hypothesis? Do the data prove that this hypothesis is correct? What fallacy might be involved in accepting the hypothesis?

Case in Point: Does Baldness Cause Heart Disease?

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A website called embarrassingproblems.com received the following email:

“Dear Dr. Margaret,

“I seem to be going bald. According to your website, this means I’m more likely to have a heart attack. If I take a drug to prevent hair loss, will it reduce my risk of a heart attack?”

What did Dr. Margaret answer? Most importantly, she did not recommend that the questioner take drugs to treat his baldness, because doctors do not think that the baldness causes the heart disease. A more likely explanation for the association between baldness and heart disease is that both conditions are affected by an underlying factor. While noting that more research needs to be done, one hypothesis that Dr. Margaret offers is that higher testosterone levels might be triggering both the hair loss and the heart disease. The good news for people with early balding (which is really where the association with increased risk of heart disease has been observed) is that they have a signal that might lead them to be checked early on for heart disease.

Source: http://www.embarrassingproblems.com/problems/problempage230701.htm. No longer posted.

Answer to Try It! Problem

The data are consistent with the hypothesis, but it is never possible to prove that a hypothesis is correct. Accepting the hypothesis could involve the fallacy of false cause; students who major in economics may already have the analytical skills needed to do well on the exam.

Labor

Labor is the human effort that can be applied to production. People who work to repair tires, pilot airplanes, teach children, or enforce laws are all part of the economy’s labor. People who would like to work but have not found employment—who are unemployed—are also considered part of the labor available to the economy.

In some contexts, it is useful to distinguish two forms of labor. The first is the human equivalent of a natural resource. It is the natural ability an untrained, uneducated person brings to a particular production process. But most workers bring far more. Skills a worker has as a result of education, training, or experience that can be used in production are called human capitalThe skills a worker has as a result of education, training, or experience that can be used in production.. Students are acquiring human capital. Workers who are gaining skills through experience or through training are acquiring human capital.

The amount of labor available to an economy can be increased in two ways. One is to increase the total quantity of labor, either by increasing the number of people available to work or by increasing the average number of hours of work per time period. The other is to increase the amount of human capital possessed by workers.

Capital

Long ago, when the first human beings walked the earth, they produced food by picking leaves or fruit off a plant or by catching an animal and eating it. We know that very early on, however, they began shaping stones into tools, apparently for use in butchering animals. Those tools were the first capital because they were produced for use in producing other goods—food and clothing.

Modern versions of the first stone tools include saws, meat cleavers, hooks, and grinders; all are used in butchering animals. Tools such as hammers, screwdrivers, and wrenches are also capital. Transportation equipment, such as cars and trucks, is capital. Facilities such as roads, bridges, ports, and airports are capital. Buildings, too, are capital; they help us to produce goods and services.

Capital does not consist solely of physical objects. The score for a new symphony is capital because it will be used to produce concerts. Computer software used by business firms or government agencies to produce goods and services is capital. Capital may thus include physical goods and intellectual discoveries. Any resource is capital if it satisfies two criteria:

1. The resource must have been produced.
2. The resource can be used to produce other goods and services.

One thing that is not considered capital is money. A firm cannot use money directly to produce other goods, so money does not satisfy the second criterion for capital. Firms can, however, use money to acquire capital. Money is a form of financial capital. Financial capitalIncludes money and other “paper” assets (such as stocks and bonds) that represent claims on future payments. includes money and other “paper” assets (such as stocks and bonds) that represent claims on future payments. These financial assets are not capital, but they can be used directly or indirectly to purchase factors of production or goods and services.

Natural Resources

There are two essential characteristics of natural resources. The first is that they are found in nature—that no human effort has been used to make or alter them. The second is that they can be used for the production of goods and services. That requires knowledge; we must know how to use the things we find in nature before they become resources.

Consider oil. Oil in the ground is a natural resource because it is found (not manufactured) and can be used to produce goods and services. However, 250 years ago oil was a nuisance, not a natural resource. Pennsylvania farmers in the eighteenth century who found oil oozing up through their soil were dismayed, not delighted. No one knew what could be done with the oil. It was not until the mid-nineteenth century that a method was found for refining oil into kerosene that could be used to generate energy, transforming oil into a natural resource. Oil is now used to make all sorts of things, including clothing, drugs, gasoline, and plastic. It became a natural resource because people discovered and implemented a way to use it.

Defining something as a natural resource only if it can be used to produce goods and services does not mean that a tree has value only for its wood or that a mountain has value only for its minerals. If people gain utility from the existence of a beautiful wilderness area, then that wilderness provides a service. The wilderness is thus a natural resource.

The natural resources available to us can be expanded in three ways. One is the discovery of new natural resources, such as the discovery of a deposit of ore containing titanium. The second is the discovery of new uses for resources, as happened when new techniques allowed oil to be put to productive use or sand to be used in manufacturing computer chips. The third is the discovery of new ways to extract natural resources in order to use them. New methods of discovering and mapping oil deposits have increased the world’s supply of this important natural resource.

Technology and the Entrepreneur

Goods and services are produced using the factors of production available to the economy. Two things play a crucial role in putting these factors of production to work. The first is technologyThe knowledge that can be applied to the production of goods and services., the knowledge that can be applied to the production of goods and services. The second is an individual who plays a key role in a market economy: the entrepreneur. An entrepreneurA person who, operating within the context of a market economy, seeks to earn profits by finding new ways to organize factors of production. is a person who, operating within the context of a market economy, seeks to earn profits by finding new ways to organize factors of production. In non-market economies the role of the entrepreneur is played by bureaucrats and other decision makers who respond to incentives other than profit to guide their choices about resource allocation decisions.

The interplay of entrepreneurs and technology affects all our lives. Entrepreneurs put new technologies to work every day, changing the way factors of production are used. Farmers and factory workers, engineers and electricians, technicians and teachers all work differently than they did just a few years ago, using new technologies introduced by entrepreneurs. The music you enjoy, the books you read, the athletic equipment with which you play are produced differently than they were five years ago. The book you are reading was written and manufactured using technologies that did not exist ten years ago. We can dispute whether all the changes have made our lives better. What we cannot dispute is that they have made our lives different.

Case in Point: Technology Cuts Costs, Boosts Productivity, Profits, and Utility

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Technology can seem an abstract force in the economy—important, but invisible.

It is not invisible to the 130 people who work on a Shell Oil Company oil rig called Mars, located in the deep waters of the Gulf of Mexico, about 160 miles southwest of Pensacola, Florida. The name Mars reflects its otherworld appearance—it extends 300 feet above the water’s surface and has steel tendons that reach 3,000 feet down to extract the Gulf’s oil deposits. This facility would not exist if it were not for the development of better oil discovery methods that include three-dimensional seismic mapping techniques, satellites that locate oil from space, and drills that can make turns as drilling foremen steer them by monitoring them on computer screens from the comfort of Mars. “We don’t hit as many dry holes,” commented Shell manager Miles Barrett. As a result of these new technologies, over the past two decades, the cost of discovering a barrel of oil dropped from $20 to under $5. And the technologies continue to improve. Three-dimensional surveys are being replaced with four-dimensional ones that allow geologists to see how the oil fields change over time.

The Mars project was destroyed by Hurricane Katrina in 2005. Royal Dutch Shell completed repairs in 2006, at a cost of $200 million. But the facility is again pumping 130,000 barrels of oil per day and 150 million cubic feet of natural gas, the energy equivalent of an additional 26,000 barrels of oil. Shell announced a new Mars-like project, Mars B Olympus, in 2010. The second Mars hub will be located 100 miles south of New Orleans and is expected to begin production in 2015.

Technology is doing more than helping energy companies track oil deposits. It is changing the way soft drinks and other grocery items are delivered to retail stores. For example, when a PepsiCo delivery driver arrives at a 7-Eleven, the driver keys into a handheld computer the store’s inventory of soft drinks, chips, and other PepsiCo products. The information is transmitted to a main computer at the warehouse that begins processing the next order for that store. The result is that the driver can visit more stores in a day and PepsiCo can cover a given territory with fewer drivers and trucks.

New technology is even helping to produce more milk from cows. Ed Larsen, who owns a 1,200-cow dairy farm in Wisconsin, never gets up before dawn to milk the cows, the way he did as a boy. Rather, the cows are hooked up to electronic milkers. Computers measure each cow’s output, and cows producing little milk are sent to a “hospital wing” for treatment. With the help of such technology, as well as better feed, today’s dairy cows produce 50% more milk than did cows roughly 20 years ago. Even though the number of dairy cows in the United States in the last 20 years has fallen 17%, milk output has increased 25%.

Who benefits from technological progress? Consumers gain from lower prices and better service. Workers gain: Their greater ability to produce goods and services translates into higher wages. And firms gain: Lower production costs mean higher profits. Of course, some people lose as technology advances. Some jobs are eliminated, and some firms find their services are no longer needed. One can argue about whether particular technological changes have improved our lives, but they have clearly made—and will continue to make—them far different.

Sources: David Ballingrud, “Drilling in the Gulf: Life on Mars,” St. Petersburg Times (Florida), August 5, 2001, p. 1A; Barbara Hagenbaugh, “Dairy Farms Evolve to Survive,” USA Today, August 7, 2003, p. 1B; Del Jones and Barbara Hansen, “Special Report: A Who’s Who of Productivity,” USA Today, August 30, 2001, p. 1B; Christopher Helman, Shell Shocked, Forbes Online, July 27, 2006; “Shell Plans Second Deep Water Production Hub,” September 9, 2010 at http://www.greentechmedia.com/industry/read/shell-plans-second-deep-water-production-hub-in-the-gulfs-pro-15227/.

Constructing a Production Possibilities Curve

To construct a production possibilities curve, we will begin with the case of a hypothetical firm, Alpine Sports, Inc., a specialized sports equipment manufacturer. Christie Ryder began the business 15 years ago with a single ski production facility near Killington ski resort in central Vermont. Ski sales grew, and she also saw demand for snowboards rising—particularly after snowboard competition events were included in the 2002 Winter Olympics in Salt Lake City. She added a second plant in a nearby town. The second plant, while smaller than the first, was designed to produce snowboards as well as skis. She also modified the first plant so that it could produce both snowboards and skis. Two years later she added a third plant in another town. While even smaller than the second plant, the third was primarily designed for snowboard production but could also produce skis.

We can think of each of Ms. Ryder’s three plants as a miniature economy and analyze them using the production possibilities model. We assume that the factors of production and technology available to each of the plants operated by Alpine Sports are unchanged.

Suppose the first plant, Plant 1, can produce 200 pairs of skis per month when it produces only skis. When devoted solely to snowboards, it produces 100 snowboards per month. It can produce skis and snowboards simultaneously as well.

The table in Figure 2.1 "A Production Possibilities Curve" gives three combinations of skis and snowboards that Plant 1 can produce each month. Combination A involves devoting the plant entirely to ski production; combination C means shifting all of the plant’s resources to snowboard production; combination B involves the production of both goods. These values are plotted in a production possibilities curve for Plant 1. The curve is a downward-sloping straight line, indicating we have assumed that there is a linear, negative relationship between the production of the two goods.

Neither skis nor snowboards is an independent or a dependent variable in the production possibilities model; we can assign either one to the vertical or to the horizontal axis. Here, we have placed the number of pairs of skis produced per month on the vertical axis and the number of snowboards produced per month on the horizontal axis.

The negative slope of the production possibilities curve reflects the scarcity of the plant’s capital and labor. Producing more snowboards requires shifting resources out of ski production and thus producing fewer skis. Producing more skis requires shifting resources out of snowboard production and thus producing fewer snowboards.

The slope of Plant 1’s production possibilities curve measures the rate at which Alpine Sports must give up ski production to produce additional snowboards. Because the production possibilities curve for Plant 1 is linear, we can compute the slope between any two points on the curve and get the same result. Between points A and B, for example, the slope equals −2 pairs of skis/snowboard (equals −100 pairs of skis/50 snowboards). (Many students are helped when told to read this result as “−2 pairs of skis per snowboard.”) We get the same value between points B and C, and between points A and C.

Figure 2.1 A Production Possibilities Curve

The table shows the combinations of pairs of skis and snowboards that Plant 1 is capable of producing each month. These are also illustrated with a production possibilities curve. Notice that this curve is linear.

To see this relationship more clearly, examine Figure 2.2 "The Slope of a Production Possibilities Curve". Suppose Plant 1 is producing 100 pairs of skis and 50 snowboards per month at point B. Now consider what would happen if Ms. Ryder decided to produce 1 more snowboard per month. The segment of the curve around point B is magnified in Figure 2.2 "The Slope of a Production Possibilities Curve". The slope between points B and B′ is −2 pairs of skis/snowboard. Producing 1 additional snowboard at point B′ requires giving up 2 pairs of skis. We can think of this as the opportunity cost of producing an additional snowboard at Plant 1. This opportunity cost equals the absolute value of the slope of the production possibilities curve.

Figure 2.2 The Slope of a Production Possibilities Curve

The slope of the linear production possibilities curve in Figure 2.1 "A Production Possibilities Curve" is constant; it is −2 pairs of skis/snowboard. In the section of the curve shown here, the slope can be calculated between points B and B′. Expanding snowboard production to 51 snowboards per month from 50 snowboards per month requires a reduction in ski production to 98 pairs of skis per month from 100 pairs. The slope equals −2 pairs of skis/snowboard (that is, it must give up two pairs of skis to free up the resources necessary to produce one additional snowboard). To shift from B′ to B″, Alpine Sports must give up two more pairs of skis per snowboard. The absolute value of the slope of a production possibilities curve measures the opportunity cost of an additional unit of the good on the horizontal axis measured in terms of the quantity of the good on the vertical axis that must be forgone.

The absolute value of the slope of any production possibilities curve equals the opportunity cost of an additional unit of the good on the horizontal axis. It is the amount of the good on the vertical axis that must be given up in order to free up the resources required to produce one more unit of the good on the horizontal axis. We will make use of this important fact as we continue our investigation of the production possibilities curve.

Figure 2.3 "Production Possibilities at Three Plants" shows production possibilities curves for each of the firm’s three plants. Each of the plants, if devoted entirely to snowboards, could produce 100 snowboards. Plants 2 and 3, if devoted exclusively to ski production, can produce 100 and 50 pairs of skis per month, respectively. The exhibit gives the slopes of the production possibilities curves for each plant. The opportunity cost of an additional snowboard at each plant equals the absolute values of these slopes (that is, the number of pairs of skis that must be given up per snowboard).

Figure 2.3 Production Possibilities at Three Plants

The slopes of the production possibilities curves for each plant differ. The steeper the curve, the greater the opportunity cost of an additional snowboard. Here, the opportunity cost is lowest at Plant 3 and greatest at Plant 1.

The exhibit gives the slopes of the production possibilities curves for each of the firm’s three plants. The opportunity cost of an additional snowboard at each plant equals the absolute values of these slopes. More generally, the absolute value of the slope of any production possibilities curve at any point gives the opportunity cost of an additional unit of the good on the horizontal axis, measured in terms of the number of units of the good on the vertical axis that must be forgone.

The greater the absolute value of the slope of the production possibilities curve, the greater the opportunity cost will be. The plant for which the opportunity cost of an additional snowboard is greatest is the plant with the steepest production possibilities curve; the plant for which the opportunity cost is lowest is the plant with the flattest production possibilities curve. The plant with the lowest opportunity cost of producing snowboards is Plant 3; its slope of −0.5 means that Ms. Ryder’s firm must give up half a pair of skis in that plant to produce an additional snowboard. In Plant 2, she must give up one pair of skis to gain one more snowboard. We have already seen that an additional snowboard requires giving up two pairs of skis in Plant 1.

Comparative Advantage and the Production Possibilities Curve

To construct a combined production possibilities curve for all three plants, we can begin by asking how many pairs of skis Alpine Sports could produce if it were producing only skis. To find this quantity, we add up the values at the vertical intercepts of each of the production possibilities curves in Figure 2.3 "Production Possibilities at Three Plants". These intercepts tell us the maximum number of pairs of skis each plant can produce. Plant 1 can produce 200 pairs of skis per month, Plant 2 can produce 100 pairs of skis at per month, and Plant 3 can produce 50 pairs. Alpine Sports can thus produce 350 pairs of skis per month if it devotes its resources exclusively to ski production. In that case, it produces no snowboards.

Now suppose the firm decides to produce 100 snowboards. That will require shifting one of its plants out of ski production. Which one will it choose to shift? The sensible thing for it to do is to choose the plant in which snowboards have the lowest opportunity cost—Plant 3. It has an advantage not because it can produce more snowboards than the other plants (all the plants in this example are capable of producing up to 100 snowboards per month) but because it is the least productive plant for making skis. Producing a snowboard in Plant 3 requires giving up just half a pair of skis.

Economists say that an economy has a comparative advantageIn producing a good or service, the situation that occurs if the opportunity cost of producing that good or service is lower for that economy than for any other. in producing a good or service if the opportunity cost of producing that good or service is lower for that economy than for any other. Plant 3 has a comparative advantage in snowboard production because it is the plant for which the opportunity cost of additional snowboards is lowest. To put this in terms of the production possibilities curve, Plant 3 has a comparative advantage in snowboard production (the good on the horizontal axis) because its production possibilities curve is the flattest of the three curves.

Figure 2.4 The Combined Production Possibilities Curve for Alpine Sports

The curve shown combines the production possibilities curves for each plant. At point A, Alpine Sports produces 350 pairs of skis per month and no snowboards. If the firm wishes to increase snowboard production, it will first use Plant 3, which has a comparative advantage in snowboards.

Plant 3’s comparative advantage in snowboard production makes a crucial point about the nature of comparative advantage. It need not imply that a particular plant is especially good at an activity. In our example, all three plants are equally good at snowboard production. Plant 3, though, is the least efficient of the three in ski production. Alpine thus gives up fewer skis when it produces snowboards in Plant 3. Comparative advantage thus can stem from a lack of efficiency in the production of an alternative good rather than a special proficiency in the production of the first good.

The combined production possibilities curve for the firm’s three plants is shown in Figure 2.4 "The Combined Production Possibilities Curve for Alpine Sports". We begin at point A, with all three plants producing only skis. Production totals 350 pairs of skis per month and zero snowboards. If the firm were to produce 100 snowboards at Plant 3, ski production would fall by 50 pairs per month (recall that the opportunity cost per snowboard at Plant 3 is half a pair of skis). That would bring ski production to 300 pairs, at point B. If Alpine Sports were to produce still more snowboards in a single month, it would shift production to Plant 2, the facility with the next-lowest opportunity cost. Producing 100 snowboards at Plant 2 would leave Alpine Sports producing 200 snowboards and 200 pairs of skis per month, at point C. If the firm were to switch entirely to snowboard production, Plant 1 would be the last to switch because the cost of each snowboard there is 2 pairs of skis. With all three plants producing only snowboards, the firm is at point D on the combined production possibilities curve, producing 300 snowboards per month and no skis.

Notice that this production possibilities curve, which is made up of linear segments from each assembly plant, has a bowed-out shape; the absolute value of its slope increases as Alpine Sports produces more and more snowboards. This is a result of transferring resources from the production of one good to another according to comparative advantage. We shall examine the significance of the bowed-out shape of the curve in the next section.

The Law of Increasing Opportunity Cost

We see in Figure 2.4 "The Combined Production Possibilities Curve for Alpine Sports" that, beginning at point A and producing only skis, Alpine Sports experiences higher and higher opportunity costs as it produces more snowboards. The fact that the opportunity cost of additional snowboards increases as the firm produces more of them is a reflection of an important economic law. The law of increasing opportunity costAs an economy moves along its production possibilities curve in the direction of producing more of a particular good, the opportunity cost of additional units of that good will increase. holds that as an economy moves along its production possibilities curve in the direction of producing more of a particular good, the opportunity cost of additional units of that good will increase.

We have seen the law of increasing opportunity cost at work traveling from point A toward point D on the production possibilities curve in Figure 2.4 "The Combined Production Possibilities Curve for Alpine Sports". The opportunity cost of each of the first 100 snowboards equals half a pair of skis; each of the next 100 snowboards has an opportunity cost of 1 pair of skis, and each of the last 100 snowboards has an opportunity cost of 2 pairs of skis. The law also applies as the firm shifts from snowboards to skis. Suppose it begins at point D, producing 300 snowboards per month and no skis. It can shift to ski production at a relatively low cost at first. The opportunity cost of the first 200 pairs of skis is just 100 snowboards at Plant 1, a movement from point D to point C, or 0.5 snowboards per pair of skis. We would say that Plant 1 has a comparative advantage in ski production. The next 100 pairs of skis would be produced at Plant 2, where snowboard production would fall by 100 snowboards per month. The opportunity cost of skis at Plant 2 is 1 snowboard per pair of skis. Plant 3 would be the last plant converted to ski production. There, 50 pairs of skis could be produced per month at a cost of 100 snowboards, or an opportunity cost of 2 snowboards per pair of skis.

The bowed-out shape of the production possibilities curve illustrates the law of increasing opportunity cost. Its downward slope reflects scarcity.

Figure 2.5 "Production Possibilities for the Economy" illustrates a much smoother production possibilities curve. This production possibilities curve in Panel (a) includes 10 linear segments and is almost a smooth curve. As we include more and more production units, the curve will become smoother and smoother. In an actual economy, with a tremendous number of firms and workers, it is easy to see that the production possibilities curve will be smooth. We will generally draw production possibilities curves for the economy as smooth, bowed-out curves, like the one in Panel (b). This production possibilities curve shows an economy that produces only skis and snowboards. Notice the curve still has a bowed-out shape; it still has a negative slope. Notice also that this curve has no numbers. Economists often use models such as the production possibilities model with graphs that show the general shapes of curves but that do not include specific numbers.

Figure 2.5 Production Possibilities for the Economy

As we combine the production possibilities curves for more and more units, the curve becomes smoother. It retains its negative slope and bowed-out shape. In Panel (a) we have a combined production possibilities curve for Alpine Sports, assuming that it now has 10 plants producing skis and snowboards. Even though each of the plants has a linear curve, combining them according to comparative advantage, as we did with 3 plants in Figure 2.4 "The Combined Production Possibilities Curve for Alpine Sports", produces what appears to be a smooth, nonlinear curve, even though it is made up of linear segments. In drawing production possibilities curves for the economy, we shall generally assume they are smooth and “bowed out,” as in Panel (b). This curve depicts an entire economy that produces only skis and snowboards.

Movements Along the Production Possibilities Curve

We can use the production possibilities model to examine choices in the production of goods and services. In applying the model, we assume that the economy can produce two goods, and we assume that technology and the factors of production available to the economy remain unchanged. In this section, we shall assume that the economy operates on its production possibilities curve so that an increase in the production of one good in the model implies a reduction in the production of the other.

We shall consider two goods and services: national defense and security and a category we shall call “all other goods and services.” This second category includes the entire range of goods and services the economy can produce, aside from national defense and security. Clearly, the transfer of resources to the effort to enhance national security reduces the quantity of other goods and services that can be produced. In the wake of the 9/11 attacks in 2001, nations throughout the world increased their spending for national security. This spending took a variety of forms. One, of course, was increased defense spending. Local and state governments also increased spending in an effort to prevent terrorist attacks. Airports around the world hired additional agents to inspect luggage and passengers.

The increase in resources devoted to security meant fewer “other goods and services” could be produced. In terms of the production possibilities curve in Figure 2.6 "Spending More for Security", the choice to produce more security and less of other goods and services means a movement from A to B. Of course, an economy cannot really produce security; it can only attempt to provide it. The attempt to provide it requires resources; it is in that sense that we shall speak of the economy as “producing” security.

Figure 2.6 Spending More for Security

Here, an economy that can produce two categories of goods, security and “all other goods and services,” begins at point A on its production possibilities curve. The economy produces S_A units of security and O_A units of all other goods and services per period. A movement from A to B requires shifting resources out of the production of all other goods and services and into spending on security. The increase in spending on security, to S_A units of security per period, has an opportunity cost of reduced production of all other goods and services. Production of all other goods and services falls by O_A - O_B units per period.

At point A, the economy was producing S_A units of security on the vertical axis—defense services and various forms of police protection—and O_A units of other goods and services on the horizontal axis. The decision to devote more resources to security and less to other goods and services represents the choice we discussed in the chapter introduction. In this case we have categories of goods rather than specific goods. Thus, the economy chose to increase spending on security in the effort to defeat terrorism. Since we have assumed that the economy has a fixed quantity of available resources, the increased use of resources for security and national defense necessarily reduces the number of resources available for the production of other goods and services.

The law of increasing opportunity cost tells us that, as the economy moves along the production possibilities curve in the direction of more of one good, its opportunity cost will increase. We may conclude that, as the economy moved along this curve in the direction of greater production of security, the opportunity cost of the additional security began to increase. That is because the resources transferred from the production of other goods and services to the production of security had a greater and greater comparative advantage in producing things other than security.

The production possibilities model does not tell us where on the curve a particular economy will operate. Instead, it lays out the possibilities facing the economy. Many countries, for example, chose to move along their respective production possibilities curves to produce more security and national defense and less of all other goods in the wake of 9/11. We will see in the chapter on demand and supply how choices about what to produce are made in the marketplace.

Producing on Versus Producing Inside the Production Possibilities Curve

An economy that is operating inside its production possibilities curve could, by moving onto it, produce more of all the goods and services that people value, such as food, housing, education, medical care, and music. Increasing the availability of these goods would improve the standard of living. Economists conclude that it is better to be on the production possibilities curve than inside it.

Two things could leave an economy operating at a point inside its production possibilities curve. First, the economy might fail to use fully the resources available to it. Second, it might not allocate resources on the basis of comparative advantage. In either case, production within the production possibilities curve implies the economy could improve its performance.

Idle Factors of Production

Suppose an economy fails to put all its factors of production to work. Some workers are without jobs, some buildings are without occupants, some fields are without crops. Because an economy’s production possibilities curve assumes the full use of the factors of production available to it, the failure to use some factors results in a level of production that lies inside the production possibilities curve.

If all the factors of production that are available for use under current market conditions are being utilized, the economy has achieved full employmentSituation in which all the factors of production that are available for use under current market conditions are being utilized.. An economy cannot operate on its production possibilities curve unless it has full employment.

Figure 2.7 Idle Factors and Production

The production possibilities curve shown suggests an economy that can produce two goods, food and clothing. As a result of a failure to achieve full employment, the economy operates at a point such as B, producing F_B units of food and C_B units of clothing per period. Putting its factors of production to work allows a move to the production possibilities curve, to a point such as A. The production of both goods rises.

Figure 2.7 "Idle Factors and Production" shows an economy that can produce food and clothing. If it chooses to produce at point A, for example, it can produce F_A units of food and C_A units of clothing. Now suppose that a large fraction of the economy’s workers lose their jobs, so the economy no longer makes full use of one factor of production: labor. In this example, production moves to point B, where the economy produces less food (F_B) and less clothing (C_B) than at point A. We often think of the loss of jobs in terms of the workers; they have lost a chance to work and to earn income. But the production possibilities model points to another loss: goods and services the economy could have produced that are not being produced.

Inefficient Production

Now suppose Alpine Sports is fully employing its factors of production. Could it still operate inside its production possibilities curve? Could an economy that is using all its factors of production still produce less than it could? The answer is “Yes,” and the key lies in comparative advantage. An economy achieves a point on its production possibilities curve only if it allocates its factors of production on the basis of comparative advantage. If it fails to do that, it will operate inside the curve.

Suppose that, as before, Alpine Sports has been producing only skis. With all three of its plants producing skis, it can produce 350 pairs of skis per month (and no snowboards). The firm then starts producing snowboards. This time, however, imagine that Alpine Sports switches plants from skis to snowboards in numerical order: Plant 1 first, Plant 2 second, and then Plant 3. Figure 2.8 "Efficient Versus Inefficient Production" illustrates the result. Instead of the bowed-out production possibilities curve ABCD, we get a bowed-in curve, AB′C′D. Suppose that Alpine Sports is producing 100 snowboards and 150 pairs of skis at point B′. Had the firm based its production choices on comparative advantage, it would have switched Plant 3 to snowboards and then Plant 2, so it could have operated at a point such as C. It would be producing more snowboards and more pairs of skis—and using the same quantities of factors of production it was using at B′. Had the firm based its production choices on comparative advantage, it would have switched Plant 3 to snowboards and then Plant 2, so it would have operated at point C. It would be producing more snowboards and more pairs of skis—and using the same quantities of factors of production it was using at B′. When an economy is operating on its production possibilities curve, we say that it is engaging in efficient productionWhen an economy is operating on its production possibilities curve.. If it is using the same quantities of factors of production but is operating inside its production possibilities curve, it is engaging in inefficient productionSituation in which the economy is using the same quantities of factors of production but is operating inside its production possibilities curve.. Inefficient production implies that the economy could be producing more goods without using any additional labor, capital, or natural resources.

Figure 2.8 Efficient Versus Inefficient Production

When factors of production are allocated on a basis other than comparative advantage, the result is inefficient production. Suppose Alpine Sports operates the three plants we examined in Figure 2.3 "Production Possibilities at Three Plants". Suppose further that all three plants are devoted exclusively to ski production; the firm operates at A. Now suppose that, to increase snowboard production, it transfers plants in numerical order: Plant 1 first, then Plant 2, and finally Plant 3. The result is the bowed-in curve AB′C′D. Production on the production possibilities curve ABCD requires that factors of production be transferred according to comparative advantage.

Points on the production possibilities curve thus satisfy two conditions: the economy is making full use of its factors of production, and it is making efficient use of its factors of production. If there are idle or inefficiently allocated factors of production, the economy will operate inside the production possibilities curve. Thus, the production possibilities curve not only shows what can be produced; it provides insight into how goods and services should be produced. It suggests that to obtain efficiency in production, factors of production should be allocated on the basis of comparative advantage. Further, the economy must make full use of its factors of production if it is to produce the goods and services it is capable of producing.

Specialization

The production possibilities model suggests that specialization will occur. SpecializationSituation in which an economy is producing the goods and services in which it has a comparative advantage. implies that an economy is producing the goods and services in which it has a comparative advantage. If Alpine Sports selects point C in Figure 2.8 "Efficient Versus Inefficient Production", for example, it will assign Plant 1 exclusively to ski production and Plants 2 and 3 exclusively to snowboard production.

Such specialization is typical in an economic system. Workers, for example, specialize in particular fields in which they have a comparative advantage. People work and use the income they earn to buy—perhaps import—goods and services from people who have a comparative advantage in doing other things. The result is a far greater quantity of goods and services than would be available without this specialization.

Think about what life would be like without specialization. Imagine that you are suddenly completely cut off from the rest of the economy. You must produce everything you consume; you obtain nothing from anyone else. Would you be able to consume what you consume now? Clearly not. It is hard to imagine that most of us could even survive in such a setting. The gains we achieve through specialization are enormous.

Nations specialize as well. Much of the land in the United States has a comparative advantage in agricultural production and is devoted to that activity. Hong Kong, with its huge population and tiny endowment of land, allocates virtually none of its land to agricultural use; that option would be too costly. Its land is devoted largely to nonagricultural use.

Key Takeaways

• A production possibilities curve shows the combinations of two goods an economy is capable of producing.
• The downward slope of the production possibilities curve is an implication of scarcity.
• The bowed-out shape of the production possibilities curve results from allocating resources based on comparative advantage. Such an allocation implies that the law of increasing opportunity cost will hold.
• An economy that fails to make full and efficient use of its factors of production will operate inside its production possibilities curve.
• Specialization means that an economy is producing the goods and services in which it has a comparative advantage.

Try It!

Suppose a manufacturing firm is equipped to produce radios or calculators. It has two plants, Plant R and Plant S, at which it can produce these goods. Given the labor and the capital available at both plants, it can produce the combinations of the two goods at the two plants shown.

Output per day, Plant R
Combination	Calculators	Radios
A	100	0
B	50	25
C	0	50

Output per day, Plant S
Combination	Calculators	Radios
D	50	0
E	25	50
F	0	100

Put calculators on the vertical axis and radios on the horizontal axis. Draw the production possibilities curve for Plant R. On a separate graph, draw the production possibilities curve for Plant S. Which plant has a comparative advantage in calculators? In radios? Now draw the combined curves for the two plants. Suppose the firm decides to produce 100 radios. Where will it produce them? How many calculators will it be able to produce? Where will it produce the calculators?

Case in Point: The Cost of the Great Depression

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The U.S. economy looked very healthy in the beginning of 1929. It had enjoyed seven years of dramatic growth and unprecedented prosperity. Its resources were fully employed; it was operating quite close to its production possibilities curve.

In the summer of 1929, however, things started going wrong. Production and employment fell. They continued to fall for several years. By 1933, more than 25% of the nation’s workers had lost their jobs. Production had plummeted by almost 30%. The economy had moved well within its production possibilities curve.

Output began to grow after 1933, but the economy continued to have vast numbers of idle workers, idle factories, and idle farms. These resources were not put back to work fully until 1942, after the U.S. entry into World War II demanded mobilization of the economy’s factors of production.

Between 1929 and 1942, the economy produced 25% fewer goods and services than it would have if its resources had been fully employed. That was a loss, measured in today’s dollars, of well over $3 trillion. In material terms, the forgone output represented a greater cost than the United States would ultimately spend in World War II. The Great Depression was a costly experience indeed.

Answer to Try It! Problem

The production possibilities curves for the two plants are shown, along with the combined curve for both plants. Plant R has a comparative advantage in producing calculators. Plant S has a comparative advantage in producing radios, so, if the firm goes from producing 150 calculators and no radios to producing 100 radios, it will produce them at Plant S. In the production possibilities curve for both plants, the firm would be at M, producing 100 calculators at Plant R.

Comparative Advantage and International Trade

One of the most important implications of the concepts of comparative advantage and the production possibilities curve relates to international trade. We can think of different nations as being equivalent to Christie Ryder’s plants. Each will have a comparative advantage in certain activities, and efficient world production requires that each nation specialize in those activities in which it has a comparative advantage. A failure to allocate resources in this way means that world production falls inside the production possibilities curve; more of each good could be produced by relying on comparative advantage.

If nations specialize, then they must rely on each other. They will sell the goods in which they specialize and purchase other goods from other nations. Suppose, for example, that the world consists of two continents that can each produce two goods: South America and Europe can produce food and computers. Suppose they can produce the two goods according to the tables in Panels (a) and (b) of Figure 2.9 "Production Possibilities Curves and Trade". We have simplified this example by assuming that each continent has a linear production possibilities curve; the curves are plotted below the tables in Panels (a) and (b). Each continent has a separate production possibilities curve; the two have been combined to illustrate a world production possibilities curve in Panel (c) of the exhibit.

Figure 2.9 Production Possibilities Curves and Trade

Suppose the world consists of two continents: South America and Europe. They can each produce two goods: food and computers. In this example, we assume that each continent has a linear production possibilities curve, as shown in Panels (a) and (b). South America has a comparative advantage in food production and Europe has a comparative advantage in computer production. With free trade, the world can operate on the bowed-out curve GHI, shown in Panel (c). If the continents refuse to trade, the world will operate inside its production possibilities curve. If, for example, each continent were to produce at the midpoint of its production possibilities curve, the world would produce 300 computers and 300 units of food per period at point Q. If each continent were to specialize in the good in which it has a comparative advantage, world production could move to a point such as H, with more of both goods produced.

The world production possibilities curve assumes that resources are allocated between computer and food production based on comparative advantage. Notice that, even with only two economies and the assumption of linear production possibilities curves for each, the combined curve still has a bowed-out shape. At point H, for example, South America specializes in food, while Europe produces only computers. World production equals 400 units of each good. In this situation, we would expect South America to export food to Europe while Europe exports computers to South America.

But suppose the regions refuse to trade; each insists on producing its own food and computers. Suppose further that each chooses to produce at the midpoint of its own production possibilities curve. South America produces 100 units of computers and 200 units of food per period, while Europe produces 200 units of computers and 100 units of food per period. World production thus totals 300 units of each good per period; the world operates at point Q in Figure 2.9 "Production Possibilities Curves and Trade". If the two continents were willing to move from isolation to trade, the world could achieve an increase in the production of both goods. Producing at point H requires no more resources, no more effort than production at Q. It does, however, require that the world’s resources be allocated on the basis of comparative advantage.

The implications of our model for trade are powerful indeed. First, we see that trade allows the production of more of all goods and services. Restrictions on trade thus reduce production of goods and services. Second, we see a lesson often missed in discussions of trade: a nation’s trade policy has nothing to do with its level of employment of its factors of production. In our example, when South America and Europe do not engage in trade and produce at the midpoints of each of their respective production possibilities curves, they each have full employment. With trade, the two nations still operate on their respective production possibilities curves: they each have full employment. Trade certainly redistributes employment in the two continents. In South America, employment shifts from computer production to food production. In Europe, it shifts from food production to computer production. Once the shift is made, though, there is no effect on employment in either continent.

Of course, this idealized example would have all of South America’s computer experts becoming farmers while all of Europe’s farmers become computer geeks! That is a bit much to swallow, but it is merely the result of assuming linear production possibilities curves and complete specialization. In the real world, production possibilities curves are concave, and the reallocation of resources required by trade is not nearly as dramatic. Still, free trade can require shifts in resources from one activity to another. These shifts produce enormous benefits, but they do not come without costs.

Nearly all economists agree that largely unrestricted trade between countries is desirable; restrictions on trade generally force the world to operate inside its production possibilities curve. In some cases restrictions on trade could be desirable, but in the main, free trade promotes greater production of goods and services for the world’s people. The role of international trade is explored in greater detail in subsequent chapters of this book.

Economic Growth

An increase in the physical quantity or in the quality of factors of production available to an economy or a technological gain will allow the economy to produce more goods and services; it will shift the economy’s production possibilities curve outward. The process through which an economy achieves an outward shift in its production possibilities curve is called economic growthThe process through which an economy achieves an outward shift in its production possibilities curve.. An outward shift in a production possibilities curve is illustrated in Figure 2.10 "Economic Growth and the Production Possibilities Curve". In Panel (a), a point such as N is not attainable; it lies outside the production possibilities curve. Growth shifts the curve outward, as in Panel (b), making previously unattainable levels of production possible.

Figure 2.10 Economic Growth and the Production Possibilities Curve

An economy capable of producing two goods, A and B, is initially operating at point M on production possibilities curve OMR in Panel (a). Given this production possibilities curve, the economy could not produce a combination such as shown by point N, which lies outside the curve. An increase in the factors of production available to the economy would shift the curve outward to SNT, allowing the choice of a point such as N, at which more of both goods will be produced.

Arenas for Choice: A Comparison of Economic Systems

Under what circumstances will a nation achieve efficiency in the use of its factors of production? The discussion above suggested that Christie Ryder would have an incentive to allocate her plants efficiently because by doing so she could achieve greater output of skis and snowboards than would be possible from inefficient production. But why would she want to produce more of these two goods—or of any goods? Why would decision makers throughout the economy want to achieve such efficiency?

Economists assume that privately owned firms seek to maximize their profits. The drive to maximize profits will lead firms such as Alpine Sports to allocate resources efficiently to gain as much production as possible from their factors of production. But whether firms will seek to maximize profits depends on the nature of the economic system within which they operate.

Classifying Economic Systems

Each of the world’s economies can be viewed as operating somewhere on a spectrum between market capitalism and command socialism. In a market capitalist economyEconomy in which resources are generally owned by private individuals who have the power to make decisions about their use., resources are generally owned by private individuals who have the power to make decisions about their use. A market capitalist system is often referred to as a free enterprise economic system. In a command socialist economyEconomy in which government is the primary owner of capital and natural resources and has broad power to allocate the use of factors of production., the government is the primary owner of capital and natural resources and has broad power to allocate the use of factors of production. Between these two categories lie mixed economiesEconomy that combine elements of market capitalist and of command socialist economic systems. that combine elements of market capitalist and of command socialist economic systems.

No economy represents a pure case of either market capitalism or command socialism. To determine where an economy lies between these two types of systems, we evaluate the extent of government ownership of capital and natural resources and the degree to which government is involved in decisions about the use of factors of production.

Figure 2.11 "Economic Systems" suggests the spectrum of economic systems. Market capitalist economies lie toward the left end of this spectrum; command socialist economies appear toward the right. Mixed economies lie in between. The market capitalist end of the spectrum includes countries such as the United States, the United Kingdom, and Chile. Hong Kong, though now part of China, has a long history as a market capitalist economy and is generally regarded as operating at the market capitalist end of the spectrum. Countries at the command socialist end of the spectrum include North Korea and Cuba.

Figure 2.11 Economic Systems

Some European economies, such as France, Germany, and Sweden, have a sufficiently high degree of regulation that we consider them as operating more toward the center of the spectrum. Russia and China, which long operated at the command socialist end of the spectrum, can now be considered mixed economies. Most economies in Latin America once operated toward the right end of the spectrum. While their governments did not exercise the extensive ownership of capital and natural resources that are one characteristic of command socialist systems, their governments did impose extensive regulations. Many of these nations are in the process of carrying out economic reforms that will move them further in the direction of market capitalism.

The global shift toward market capitalist economic systems that occurred in the 1980s and 1990s was in large part the result of three important features of such economies. First, the emphasis on individual ownership and decision-making power has generally yielded greater individual freedom than has been available under command socialist or some more heavily regulated mixed economic systems that lie toward the command socialist end of the spectrum. People seeking political, religious, and economic freedom have thus gravitated toward market capitalism. Second, market economies are more likely than other systems to allocate resources on the basis of comparative advantage. They thus tend to generate higher levels of production and income than do other economic systems. Third, market capitalist-type systems appear to be the most conducive to entrepreneurial activity.

Suppose Christie Ryder had the same three plants we considered earlier in this chapter but was operating in a mixed economic system with extensive government regulation. In such a system, she might be prohibited from transferring resources from one use to another to achieve the gains possible from comparative advantage. If she were operating under a command socialist system, she would not be the owner of the plants and thus would be unlikely to profit from their efficient use. If that were the case, there is no reason to believe she would make any effort to assure the efficient use of the three plants. Generally speaking, it is economies toward the market capitalist end of the spectrum that offer the greatest inducement to allocate resources on the basis of comparative advantage. They tend to be more productive and to deliver higher material standards of living than do economies that operate at or near the command socialist end of the spectrum.

Figure 2.12 Economic Freedom and Income

The graph shows the relationship between economic freedom and per capita income by region. Countries with higher degrees of economic freedom tended to have higher per capita incomes.

Source: Terry Miller and Kim R. Holmes, 2011 Index of Economic Freedom (Washington, D.C.: The Heritage Foundation and Dow Jones & Company, Inc., 2011), at www.heritage.org/index.

Market capitalist economies rely on economic freedom. Indeed, one way we can assess the degree to which a country can be considered market capitalist is by the degree of economic freedom it permits. Several organizations have attempted to compare economic freedom in various countries. One of the most extensive comparisons is a joint annual effort by the Heritage Foundation and the Wall Street Journal. The 2011 rating was based on policies in effect in 183 nations early that year. The report ranks these nations on the basis of such things as the degree of regulation of firms, tax levels, and restrictions on international trade. Hong Kong ranked as the freest economy in the world. North Korea received the dubious distinction of being the least free.

It seems reasonable to expect that the greater the degree of economic freedom a country permits, the greater the amount of income per person it will generate. This proposition is illustrated in Figure 2.12 "Economic Freedom and Income". The study also found a positive association between the degree of economic freedom and overall well-being using a measure that takes into account such variables as health, education, security, and personal freedom. We must be wary of slipping into the fallacy of false cause by concluding from this evidence that economic freedom generates higher incomes. It could be that higher incomes lead nations to opt for greater economic freedom. But in this case, it seems reasonable to conclude that, in general, economic freedom does lead to higher incomes.

Government in a Market Economy

The production possibilities model provides a menu of choices among alternative combinations of goods and services. Given those choices, which combinations will be produced?

In a market economy, this question is answered in large part through the interaction of individual buyers and sellers. As we have already seen, government plays a role as well. It may seek to encourage greater consumption of some goods and discourage consumption of others. In the United States, for example, taxes imposed on cigarettes discourage smoking, while special treatment of property taxes and mortgage interest in the federal income tax encourages home ownership. Government may try to stop the production and consumption of some goods altogether, as many governments do with drugs such as heroin and cocaine. Government may supplement the private consumption of some goods by producing more of them itself, as many U.S. cities do with golf courses and tennis courts. In other cases, there may be no private market for a good or service at all. In the choice between security and defense versus all other goods and services outlined at the beginning of this chapter, government agencies are virtually the sole providers of security and national defense.

All nations also rely on government to provide defense, enforce laws, and redistribute income. Even market economies rely on government to regulate the activities of private firms, to protect the environment, to provide education, and to produce a wide range of other goods and services. Government’s role may be limited in a market economy, but it remains fundamentally important.

Case in Point: The Prospects for World Economic Growth

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What will happen to world economic growth in the next 10 years? The prognosis, according to economists Dale W. Jorgenson of Harvard University and Khuong M. Vu of the National University of Singapore, suggests that world growth is likely to be somewhat slower in the next decade than it was in the last.

The two economists, who have written extensively on the problem of estimating world economic growth, estimate that the world economy (based on their sample of 122 countries that account for 95% of world GDP) grew at a rate of just 2.20% from 1990–1995. That increased to 3.37% per year from 1995–2000. During the period from 2000–2005 the annual growth rate accelerated again to 3.71%. Despite the recession and financial crisis that began in 2008, world growth slowed a bit but was still 3.06% from 2005 to 2009. Growth at 3% would double world economic income every 24 years. Think for a moment about what that implies—world income would quadruple in just 48 years. Growth at the 1990–1995 pace of 2.20% per year would take 33 years for income to double.

Might the world growth rates from 2000 to 2009 of above 3% be repeated during the next 10 years? Under their base-case scenario, the economists project the world growth rate between 2010 and 2020 to be about 3.37%.

What do they think the economic world will look like then? They predict that over the next 10-year period: the U.S. growth rate will slow down compared to the last two decades, primarily due to slower growth in labor quality, but the U.S. growth rate will still lead among the G7 countries (a group of seven large industrialized countries that includes Canada, France, Germany, Italy, Japan, the United Kingdom, and the United States); the overall growth in the G7 countries will continue to decline; and growth in the developing countries of Asia (Bangladesh Cambodia, China, Hong Kong, India, Indonesia, Malaysia, Nepal, Pakistan, Philippines, Singapore, South Korean, Sri Lanka, Taiwan, Thailand, and Vietnam) will slow a bit from the recent past but will be high enough that those countries’ GDPs will comprise nearly 37% of world GDP in 2020, as compared to 29% in 2010. In terms of size of GDP in 2020, they predict the following new order: China, the United States, India, Japan, Russia, Germany, and Brazil. If their predictions are realized, it will mark the end of a period of more than a century in which the United States has been the world’s largest economy.

Sources: Dale W. Jorgenson and Khoung M. Vu, “The Rise of Developing Asia and the New Economic Order,” Journal of Policy Modeling 33:5 (September–October 2011), forthcoming.

Answer to Try It! Problem

Your first production possibilities curve should resemble the one in Panel (a). Starting at point A, an increase in jacket production requires a move down and to the right along the curve, as shown by the arrow, and thus a reduction in the production of CD players. Alternatively, if there is economic growth, it shifts the production possibilities curve outward, as in Panel (b). This shift allows an increase in production of both goods, as suggested by the arrow.

Price and the Demand Curve

Because people will purchase different quantities of a good or service at different prices, economists must be careful when speaking of the “demand” for something. They have therefore developed some specific terms for expressing the general concept of demand.

The quantity demandedThe quantity buyers are willing and able to buy of a good or service at a particular price during a particular period, all other things unchanged. of a good or service is the quantity buyers are willing and able to buy at a particular price during a particular period, all other things unchanged. (As we learned, we can substitute the Latin phrase “ceteris paribus” for “all other things unchanged.”) Suppose, for example, that 100,000 movie tickets are sold each month in a particular town at a price of $8 per ticket. That quantity—100,000—is the quantity of movie admissions demanded per month at a price of $8. If the price were $12, we would expect the quantity demanded to be less. If it were $4, we would expect the quantity demanded to be greater. The quantity demanded at each price would be different if other things that might affect it, such as the population of the town, were to change. That is why we add the qualifier that other things have not changed to the definition of quantity demanded.

A demand scheduleA table that shows the quantities of a good or service demanded at different prices during a particular period, all other things unchanged. is a table that shows the quantities of a good or service demanded at different prices during a particular period, all other things unchanged. To introduce the concept of a demand schedule, let us consider the demand for coffee in the United States. We will ignore differences among types of coffee beans and roasts, and speak simply of coffee. The table in Figure 3.1 "A Demand Schedule and a Demand Curve" shows quantities of coffee that will be demanded each month at prices ranging from $9 to $4 per pound; the table is a demand schedule. We see that the higher the price, the lower the quantity demanded.

Figure 3.1 A Demand Schedule and a Demand Curve

The table is a demand schedule; it shows quantities of coffee demanded per month in the United States at particular prices, all other things unchanged. These data are then plotted on the demand curve. At point A on the curve, 25 million pounds of coffee per month are demanded at a price of $6 per pound. At point B, 30 million pounds of coffee per month are demanded at a price of $5 per pound.

The information given in a demand schedule can be presented with a demand curveA graphical representation of a demand schedule., which is a graphical representation of a demand schedule. A demand curve thus shows the relationship between the price and quantity demanded of a good or service during a particular period, all other things unchanged. The demand curve in Figure 3.1 "A Demand Schedule and a Demand Curve" shows the prices and quantities of coffee demanded that are given in the demand schedule. At point A, for example, we see that 25 million pounds of coffee per month are demanded at a price of $6 per pound. By convention, economists graph price on the vertical axis and quantity on the horizontal axis.

Price alone does not determine the quantity of coffee or any other good that people buy. To isolate the effect of changes in price on the quantity of a good or service demanded, however, we show the quantity demanded at each price, assuming that those other variables remain unchanged. We do the same thing in drawing a graph of the relationship between any two variables; we assume that the values of other variables that may affect the variables shown in the graph (such as income or population) remain unchanged for the period under consideration.

A change in price, with no change in any of the other variables that affect demand, results in a movement along the demand curve. For example, if the price of coffee falls from $6 to $5 per pound, consumption rises from 25 million pounds to 30 million pounds per month. That is a movement from point A to point B along the demand curve in Figure 3.1 "A Demand Schedule and a Demand Curve". A movement along a demand curve that results from a change in price is called a change in quantity demandedA movement along a demand curve that results from a change in price.. Note that a change in quantity demanded is not a change or shift in the demand curve; it is a movement along the demand curve.

The negative slope of the demand curve in Figure 3.1 "A Demand Schedule and a Demand Curve" suggests a key behavioral relationship in economics. All other things unchanged, the law of demandFor virtually all goods and services, a higher price leads to a reduction in quantity demanded and a lower price leads to an increase in quantity demanded. holds that, for virtually all goods and services, a higher price leads to a reduction in quantity demanded and a lower price leads to an increase in quantity demanded.

The law of demand is called a law because the results of countless studies are consistent with it. Undoubtedly, you have observed one manifestation of the law. When a store finds itself with an overstock of some item, such as running shoes or tomatoes, and needs to sell these items quickly, what does it do? It typically has a sale, expecting that a lower price will increase the quantity demanded. In general, we expect the law of demand to hold. Given the values of other variables that influence demand, a higher price reduces the quantity demanded. A lower price increases the quantity demanded. Demand curves, in short, slope downward.

Changes in Demand

Of course, price alone does not determine the quantity of a good or service that people consume. Coffee consumption, for example, will be affected by such variables as income and population. Preferences also play a role. The story at the beginning of the chapter illustrates how Starbucks “turned people on” to coffee. We also expect other prices to affect coffee consumption. People often eat doughnuts or bagels with their coffee, so a reduction in the price of doughnuts or bagels might induce people to drink more coffee. An alternative to coffee is tea, so a reduction in the price of tea might result in the consumption of more tea and less coffee. Thus, a change in any one of the variables held constant in constructing a demand schedule will change the quantities demanded at each price. The result will be a shift in the entire demand curve rather than a movement along the demand curve. A shift in a demand curve is called a change in demandA shift in a demand curve..

Suppose, for example, that something happens to increase the quantity of coffee demanded at each price. Several events could produce such a change: an increase in incomes, an increase in population, or an increase in the price of tea would each be likely to increase the quantity of coffee demanded at each price. Any such change produces a new demand schedule. Figure 3.2 "An Increase in Demand" shows such a change in the demand schedule for coffee. We see that the quantity of coffee demanded per month is greater at each price than before. We show that graphically as a shift in the demand curve. The original curve, labeled D₁, shifts to the right to D₂. At a price of $6 per pound, for example, the quantity demanded rises from 25 million pounds per month (point A) to 35 million pounds per month (point A′).

Figure 3.2 An Increase in Demand

An increase in the quantity of a good or service demanded at each price is shown as an increase in demand. Here, the original demand curve D₁ shifts to D₂. Point A on D₁ corresponds to a price of $6 per pound and a quantity demanded of 25 million pounds of coffee per month. On the new demand curve D₂, the quantity demanded at this price rises to 35 million pounds of coffee per month (point A′).

Just as demand can increase, it can decrease. In the case of coffee, demand might fall as a result of events such as a reduction in population, a reduction in the price of tea, or a change in preferences. For example, a definitive finding that the caffeine in coffee contributes to heart disease, which is currently being debated in the scientific community, could change preferences and reduce the demand for coffee.

A reduction in the demand for coffee is illustrated in Figure 3.3 "A Reduction in Demand". The demand schedule shows that less coffee is demanded at each price than in Figure 3.1 "A Demand Schedule and a Demand Curve". The result is a shift in demand from the original curve D₁ to D₃. The quantity of coffee demanded at a price of $6 per pound falls from 25 million pounds per month (point A) to 15 million pounds per month (point A″). Note, again, that a change in quantity demanded, ceteris paribus, refers to a movement along the demand curve, while a change in demand refers to a shift in the demand curve.

Figure 3.3 A Reduction in Demand

A reduction in demand occurs when the quantities of a good or service demanded fall at each price. Here, the demand schedule shows a lower quantity of coffee demanded at each price than we had in Figure 3.1 "A Demand Schedule and a Demand Curve". The reduction shifts the demand curve for coffee to D₃ from D₁. The quantity demanded at a price of $6 per pound, for example, falls from 25 million pounds per month (point A) to 15 million pounds of coffee per month (point A″).

A variable that can change the quantity of a good or service demanded at each price is called a demand shifterA variable that can change the quantity of a good or service demanded at each price.. When these other variables change, the all-other-things-unchanged conditions behind the original demand curve no longer hold. Although different goods and services will have different demand shifters, the demand shifters are likely to include (1) consumer preferences, (2) the prices of related goods and services, (3) income, (4) demographic characteristics, and (5) buyer expectations. Next we look at each of these.

Prices of Related Goods and Services

Suppose the price of doughnuts were to fall. Many people who drink coffee enjoy dunking doughnuts in their coffee; the lower price of doughnuts might therefore increase the demand for coffee, shifting the demand curve for coffee to the right. A lower price for tea, however, would be likely to reduce coffee demand, shifting the demand curve for coffee to the left.

In general, if a reduction in the price of one good increases the demand for another, the two goods are called complementsTwo goods for which an increase in price of one reduces the demand for the other.. If a reduction in the price of one good reduces the demand for another, the two goods are called substitutesTwo goods for which an increase in price of one increases the demand for the other.. These definitions hold in reverse as well: two goods are complements if an increase in the price of one reduces the demand for the other, and they are substitutes if an increase in the price of one increases the demand for the other. Doughnuts and coffee are complements; tea and coffee are substitutes.

Complementary goods are goods used in conjunction with one another. Tennis rackets and tennis balls, eggs and bacon, and stationery and postage stamps are complementary goods. Substitute goods are goods used instead of one another. iPODs, for example, are likely to be substitutes for CD players. Breakfast cereal is a substitute for eggs. A file attachment to an e-mail is a substitute for both a fax machine and postage stamps.

Buyer Expectations

The consumption of goods that can be easily stored, or whose consumption can be postponed, is strongly affected by buyer expectations. The expectation of newer TV technologies, such as high-definition TV, could slow down sales of regular TVs. If people expect gasoline prices to rise tomorrow, they will fill up their tanks today to try to beat the price increase. The same will be true for goods such as automobiles and washing machines: an expectation of higher prices in the future will lead to more purchases today. If the price of a good is expected to fall, however, people are likely to reduce their purchases today and await tomorrow’s lower prices. The expectation that computer prices will fall, for example, can reduce current demand.

Heads Up!

It is crucial to distinguish between a change in quantity demanded, which is a movement along the demand curve caused by a change in price, and a change in demand, which implies a shift of the demand curve itself. A change in demand is caused by a change in a demand shifter. An increase in demand is a shift of the demand curve to the right. A decrease in demand is a shift in the demand curve to the left. This drawing of a demand curve highlights the difference.

Key Takeaways

• The quantity demanded of a good or service is the quantity buyers are willing and able to buy at a particular price during a particular period, all other things unchanged.
• A demand schedule is a table that shows the quantities of a good or service demanded at different prices during a particular period, all other things unchanged.
• A demand curve shows graphically the quantities of a good or service demanded at different prices during a particular period, all other things unchanged.
• All other things unchanged, the law of demand holds that, for virtually all goods and services, a higher price induces a reduction in quantity demanded and a lower price induces an increase in quantity demanded.
• A change in the price of a good or service causes a change in the quantity demanded—a movement along the demand curve.
• A change in a demand shifter causes a change in demand, which is shown as a shift of the demand curve. Demand shifters include preferences, the prices of related goods and services, income, demographic characteristics, and buyer expectations.
• Two goods are substitutes if an increase in the price of one causes an increase in the demand for the other. Two goods are complements if an increase in the price of one causes a decrease in the demand for the other.
• A good is a normal good if an increase in income causes an increase in demand. A good is an inferior good if an increase in income causes a decrease in demand.

Try It!

All other things unchanged, what happens to the demand curve for DVD rentals if there is (a) an increase in the price of movie theater tickets, (b) a decrease in family income, or (c) an increase in the price of DVD rentals? In answering this and other “Try It!” problems in this chapter, draw and carefully label a set of axes. On the horizontal axis of your graph, show the quantity of DVD rentals. It is necessary to specify the time period to which your quantity pertains (e.g., “per period,” “per week,” or “per year”). On the vertical axis show the price per DVD rental. Since you do not have specific data on prices and quantities demanded, make a “free-hand” drawing of the curve or curves you are asked to examine. Focus on the general shape and position of the curve(s) before and after events occur. Draw new curve(s) to show what happens in each of the circumstances given. The curves could shift to the left or to the right, or stay where they are.

Case in Point: Solving Campus Parking Problems Without Adding More Parking Spaces

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Unless you attend a “virtual” campus, chances are you have engaged in more than one conversation about how hard it is to find a place to park on campus. Indeed, according to Clark Kerr, a former president of the University of California system, a university is best understood as a group of people “held together by a common grievance over parking.”

Clearly, the demand for campus parking spaces has grown substantially over the past few decades. In surveys conducted by Daniel Kenney, Ricardo Dumont, and Ginger Kenney, who work for the campus design company Sasaki and Associates, it was found that 7 out of 10 students own their own cars. They have interviewed “many students who confessed to driving from their dormitories to classes that were a five-minute walk away,” and they argue that the deterioration of college environments is largely attributable to the increased use of cars on campus and that colleges could better service their missions by not adding more parking spaces.

Since few universities charge enough for parking to even cover the cost of building and maintaining parking lots, the rest is paid for by all students as part of tuition. Their research shows that “for every 1,000 parking spaces, the median institution loses almost $400,000 a year for surface parking, and more than $1,200,000 for structural parking.” Fear of a backlash from students and their parents, as well as from faculty and staff, seems to explain why campus administrators do not simply raise the price of parking on campus.

While Kenney and his colleagues do advocate raising parking fees, if not all at once then over time, they also suggest some subtler, and perhaps politically more palatable, measures—in particular, shifting the demand for parking spaces to the left by lowering the prices of substitutes.

Two examples they noted were at the University of Washington and the University of Colorado at Boulder. At the University of Washington, car poolers may park for free. This innovation has reduced purchases of single-occupancy parking permits by 32% over a decade. According to University of Washington assistant director of transportation services Peter Dewey, “Without vigorously managing our parking and providing commuter alternatives, the university would have been faced with adding approximately 3,600 parking spaces, at a cost of over $100 million…The university has created opportunities to make capital investments in buildings supporting education instead of structures for cars.” At the University of Colorado, free public transit has increased use of buses and light rail from 300,000 to 2 million trips per year over the last decade. The increased use of mass transit has allowed the university to avoid constructing nearly 2,000 parking spaces, which has saved about $3.6 million annually.

Sources: Daniel R. Kenney, “How to Solve Campus Parking Problems Without Adding More Parking,” The Chronicle of Higher Education, March 26, 2004, Section B, pp. B22-B23.

Answer to Try It! Problem

Since going to the movies is a substitute for watching a DVD at home, an increase in the price of going to the movies should cause more people to switch from going to the movies to staying at home and renting DVDs. Thus, the demand curve for DVD rentals will shift to the right when the price of movie theater tickets increases [Panel (a)].

A decrease in family income will cause the demand curve to shift to the left if DVD rentals are a normal good but to the right if DVD rentals are an inferior good. The latter may be the case for some families, since staying at home and watching DVDs is a cheaper form of entertainment than taking the family to the movies. For most others, however, DVD rentals are probably a normal good [Panel (b)].

An increase in the price of DVD rentals does not shift the demand curve for DVD rentals at all; rather, an increase in price, say from P₁ to P₂, is a movement upward to the left along the demand curve. At a higher price, people will rent fewer DVDs, say Q₂ instead of Q₁, ceteris paribus [Panel (c)].

Price and the Supply Curve

The quantity suppliedThe quantity sellers are willing to sell of a good or service at a particular price during a particular period, all other things unchanged. of a good or service is the quantity sellers are willing to sell at a particular price during a particular period, all other things unchanged. Ceteris paribus, the receipt of a higher price increases profits and induces sellers to increase the quantity they supply.

In general, when there are many sellers of a good, an increase in price results in an increase in quantity supplied, and this relationship is often referred to as the law of supply. We will see, though, through our exploration of microeconomics, that there are a number of exceptions to this relationship. There are cases in which a higher price will not induce an increase in quantity supplied. Goods that cannot be produced, such as additional land on the corner of Park Avenue and 56th Street in Manhattan, are fixed in supply—a higher price cannot induce an increase in the quantity supplied. There are even cases, which we investigate in microeconomic analysis, in which a higher price induces a reduction in the quantity supplied.

Generally speaking, however, when there are many sellers of a good, an increase in price results in a greater quantity supplied. The relationship between price and quantity supplied is suggested in a supply scheduleA table that shows quantities supplied at different prices during a particular period, all other things unchanged., a table that shows quantities supplied at different prices during a particular period, all other things unchanged. Figure 3.4 "A Supply Schedule and a Supply Curve" gives a supply schedule for the quantities of coffee that will be supplied per month at various prices, ceteris paribus. At a price of $4 per pound, for example, producers are willing to supply 15 million pounds of coffee per month. A higher price, say $6 per pound, induces sellers to supply a greater quantity—25 million pounds of coffee per month.

Figure 3.4 A Supply Schedule and a Supply Curve

The supply schedule shows the quantity of coffee that will be supplied in the United States each month at particular prices, all other things unchanged. The same information is given graphically in the supply curve. The values given here suggest a positive relationship between price and quantity supplied.

A supply curveA graphical representation of a supply schedule. is a graphical representation of a supply schedule. It shows the relationship between price and quantity supplied during a particular period, all other things unchanged. Because the relationship between price and quantity supplied is generally positive, supply curves are generally upward sloping. The supply curve for coffee in Figure 3.4 "A Supply Schedule and a Supply Curve" shows graphically the values given in the supply schedule.

A change in price causes a movement along the supply curve; such a movement is called a change in quantity suppliedMovement along the supply curve caused by a change in price.. As is the case with a change in quantity demanded, a change in quantity supplied does not shift the supply curve. By definition, it is a movement along the supply curve. For example, if the price rises from $6 per pound to $7 per pound, the quantity supplied rises from 25 million pounds per month to 30 million pounds per month. That’s a movement from point A to point B along the supply curve in Figure 3.4 "A Supply Schedule and a Supply Curve".

Changes in Supply

When we draw a supply curve, we assume that other variables that affect the willingness of sellers to supply a good or service are unchanged. It follows that a change in any of those variables will cause a change in supplyA shift in the supply curve., which is a shift in the supply curve. A change that increases the quantity of a good or service supplied at each price shifts the supply curve to the right. Suppose, for example, that the price of fertilizer falls. That will reduce the cost of producing coffee and thus increase the quantity of coffee producers will offer for sale at each price. The supply schedule in Figure 3.5 "An Increase in Supply" shows an increase in the quantity of coffee supplied at each price. We show that increase graphically as a shift in the supply curve from S₁ to S₂. We see that the quantity supplied at each price increases by 10 million pounds of coffee per month. At point A on the original supply curve S₁, for example, 25 million pounds of coffee per month are supplied at a price of $6 per pound. After the increase in supply, 35 million pounds per month are supplied at the same price (point A′ on curve S₂).

Figure 3.5 An Increase in Supply

If there is a change in supply that increases the quantity supplied at each price, as is the case in the supply schedule here, the supply curve shifts to the right. At a price of $6 per pound, for example, the quantity supplied rises from the previous level of 25 million pounds per month on supply curve S₁ (point A) to 35 million pounds per month on supply curve S₂ (point A′).

An event that reduces the quantity supplied at each price shifts the supply curve to the left. An increase in production costs and excessive rain that reduces the yields from coffee plants are examples of events that might reduce supply. Figure 3.6 "A Reduction in Supply" shows a reduction in the supply of coffee. We see in the supply schedule that the quantity of coffee supplied falls by 10 million pounds of coffee per month at each price. The supply curve thus shifts from S₁ to S₃.

Figure 3.6 A Reduction in Supply

A change in supply that reduces the quantity supplied at each price shifts the supply curve to the left. At a price of $6 per pound, for example, the original quantity supplied was 25 million pounds of coffee per month (point A). With a new supply curve S₃, the quantity supplied at that price falls to 15 million pounds of coffee per month (point A″).

A variable that can change the quantity of a good or service supplied at each price is called a supply shifterA variable that can change the quantity of a good or service supplied at each price.. Supply shifters include (1) prices of factors of production, (2) returns from alternative activities, (3) technology, (4) seller expectations, (5) natural events, and (6) the number of sellers. When these other variables change, the all-other-things-unchanged conditions behind the original supply curve no longer hold. Let us look at each of the supply shifters.

The Number of Sellers

The supply curve for an industry, such as coffee, includes all the sellers in the industry. A change in the number of sellers in an industry changes the quantity available at each price and thus changes supply. An increase in the number of sellers supplying a good or service shifts the supply curve to the right; a reduction in the number of sellers shifts the supply curve to the left.

The market for cellular phone service has been affected by an increase in the number of firms offering the service. Over the past decade, new cellular phone companies emerged, shifting the supply curve for cellular phone service to the right.

Heads Up!

There are two special things to note about supply curves. The first is similar to the Heads Up! on demand curves: it is important to distinguish carefully between changes in supply and changes in quantity supplied. A change in supply results from a change in a supply shifter and implies a shift of the supply curve to the right or left. A change in price produces a change in quantity supplied and induces a movement along the supply curve. A change in price does not shift the supply curve.

The second caution relates to the interpretation of increases and decreases in supply. Notice that in Figure 3.5 "An Increase in Supply" an increase in supply is shown as a shift of the supply curve to the right; the curve shifts in the direction of increasing quantity with respect to the horizontal axis. In Figure 3.6 "A Reduction in Supply" a reduction in supply is shown as a shift of the supply curve to the left; the curve shifts in the direction of decreasing quantity with respect to the horizontal axis.

Because the supply curve is upward sloping, a shift to the right produces a new curve that in a sense lies “below” the original curve. It is easy to make the mistake of thinking of such a shift as a shift “down” and therefore as a reduction in supply. Similarly, it is easy to make the mistake of showing an increase in supply with a new curve that lies “above” the original curve. But that is a reduction in supply!

To avoid such errors, focus on the fact that an increase in supply is an increase in the quantity supplied at each price and shifts the supply curve in the direction of increased quantity on the horizontal axis. Similarly, a reduction in supply is a reduction in the quantity supplied at each price and shifts the supply curve in the direction of a lower quantity on the horizontal axis.

Key Takeaways

• The quantity supplied of a good or service is the quantity sellers are willing to sell at a particular price during a particular period, all other things unchanged.
• A supply schedule shows the quantities supplied at different prices during a particular period, all other things unchanged. A supply curve shows this same information graphically.
• A change in the price of a good or service causes a change in the quantity supplied—a movement along the supply curve.
• A change in a supply shifter causes a change in supply, which is shown as a shift of the supply curve. Supply shifters include prices of factors of production, returns from alternative activities, technology, seller expectations, natural events, and the number of sellers.
• An increase in supply is shown as a shift to the right of a supply curve; a decrease in supply is shown as a shift to the left.

Try It!

If all other things are unchanged, what happens to the supply curve for DVD rentals if there is (a) an increase in wages paid to DVD rental store clerks, (b) an increase in the price of DVD rentals, or (c) an increase in the number of DVD rental stores? Draw a graph that shows what happens to the supply curve in each circumstance. The supply curve can shift to the left or to the right, or stay where it is. Remember to label the axes and curves, and remember to specify the time period (e.g., “DVDs rented per week”).

Case in Point: The Monks of St. Benedict’s Get Out of the Egg Business

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It was cookies that lured the monks of St. Benedict’s out of the egg business, and now private retreat sponsorship is luring them away from cookies.

St. Benedict’s is a Benedictine monastery, nestled on a ranch high in the Colorado Rockies, about 20 miles down the road from Aspen. The monastery’s 20 monks operate the ranch to support themselves and to provide help for poor people in the area. They lease out about 3,500 acres of their land to cattle and sheep grazers, produce cookies, and sponsor private retreats. They used to produce eggs.

Attracted by potential profits and the peaceful nature of the work, the monks went into the egg business in 1967. They had 10,000 chickens producing their Monastery Eggs brand. For a while, business was good. Very good. Then, in the late 1970s, the price of chicken feed started to rise rapidly.

“When we started in the business, we were paying $60 to $80 a ton for feed—delivered,” recalls the monastery’s abbot, Father Joseph Boyle. “By the late 1970s, our cost had more than doubled. We were paying $160 to $200 a ton. That really hurt, because feed represents a large part of the cost of producing eggs.”

The monks adjusted to the blow. “When grain prices were lower, we’d pull a hen off for a few weeks to molt, then return her to laying. After grain prices went up, it was 12 months of laying and into the soup pot,” Fr. Joseph says.

Grain prices continued to rise in the 1980s and increased the costs of production for all egg producers. It caused the supply of eggs to fall. Demand fell at the same time, as Americans worried about the cholesterol in eggs. Times got tougher in the egg business.

“We were still making money in the financial sense,” Fr. Joseph says. “But we tried an experiment in 1985 producing cookies, and it was a success. We finally decided that devoting our time and energy to the cookies would pay off better than the egg business, so we quit the egg business in 1986.”

The mail-order cookie business was good to the monks. They sold 200,000 ounces of Monastery Cookies in 1987.

By 1998, however, they had limited their production of cookies, selling only locally and to gift shops. Since 2000, they have switched to “providing private retreats for individuals and groups—about 40 people per month,” according to Fr. Micah Schonberger.

The monks’ calculation of their opportunity costs revealed that they would earn a higher return through sponsorship of private retreats than in either cookies or eggs. This projection has proved correct.

And there is another advantage as well.

“The chickens didn’t stop laying eggs on Sunday,” Fr. Joseph chuckles. “When we shifted to cookies we could take Sundays off. We weren’t hemmed in the way we were with the chickens.” The move to providing retreats is even better in this regard. Since guests provide their own meals, most of the monastery’s effort goes into planning and scheduling, which frees up even more of their time for other worldly as well as spiritual pursuits.

Source: Personal interviews and the monastery’s website at http://www.snowmass.org.

Answer to Try It! Problem

DVD rental store clerks are a factor of production in the DVD rental market. An increase in their wages raises the cost of production, thereby causing the supply curve of DVD rentals to shift to the left [Panel (a)]. (Caution: It is possible that you thought of the wage increase as an increase in income, a demand shifter, that would lead to an increase in demand, but this would be incorrect. The question refers only to wages of DVD rental store clerks. They may rent some DVD, but their impact on total demand would be negligible. Besides, we have no information on what has happened overall to incomes of people who rent DVDs. We do know, however, that the cost of a factor of production, which is a supply shifter, increased.)

An increase in the price of DVD rentals does not shift the supply curve at all; rather, it corresponds to a movement upward to the right along the supply curve. At a higher price of P₂ instead of P₁, a greater quantity of DVD rentals, say Q₂ instead of Q₁, will be supplied [Panel (b)].

An increase in the number of stores renting DVDs will cause the supply curve to shift to the right [Panel (c)].

The Determination of Price and Quantity

The logic of the model of demand and supply is simple. The demand curve shows the quantities of a particular good or service that buyers will be willing and able to purchase at each price during a specified period. The supply curve shows the quantities that sellers will offer for sale at each price during that same period. By putting the two curves together, we should be able to find a price at which the quantity buyers are willing and able to purchase equals the quantity sellers will offer for sale.

Figure 3.7 "The Determination of Equilibrium Price and Quantity" combines the demand and supply data introduced in Figure 3.1 "A Demand Schedule and a Demand Curve" and Figure 3.4 "A Supply Schedule and a Supply Curve". Notice that the two curves intersect at a price of $6 per pound—at this price the quantities demanded and supplied are equal. Buyers want to purchase, and sellers are willing to offer for sale, 25 million pounds of coffee per month. The market for coffee is in equilibrium. Unless the demand or supply curve shifts, there will be no tendency for price to change. The equilibrium priceThe price at which quantity demanded equals quantity supplied. in any market is the price at which quantity demanded equals quantity supplied. The equilibrium price in the market for coffee is thus $6 per pound. The equilibrium quantityThe quantity demanded and supplied at the equilibrium price. is the quantity demanded and supplied at the equilibrium price. At a price above the equilibrium, there is a natural tendency for the price to fall. At a price below the equilibrium, there is a tendency for the price to rise.

Figure 3.7 The Determination of Equilibrium Price and Quantity

When we combine the demand and supply curves for a good in a single graph, the point at which they intersect identifies the equilibrium price and equilibrium quantity. Here, the equilibrium price is $6 per pound. Consumers demand, and suppliers supply, 25 million pounds of coffee per month at this price.

With an upward-sloping supply curve and a downward-sloping demand curve, there is only a single price at which the two curves intersect. This means there is only one price at which equilibrium is achieved. It follows that at any price other than the equilibrium price, the market will not be in equilibrium. We next examine what happens at prices other than the equilibrium price.

Surpluses

Figure 3.8 "A Surplus in the Market for Coffee" shows the same demand and supply curves we have just examined, but this time the initial price is $8 per pound of coffee. Because we no longer have a balance between quantity demanded and quantity supplied, this price is not the equilibrium price. At a price of $8, we read over to the demand curve to determine the quantity of coffee consumers will be willing to buy—15 million pounds per month. The supply curve tells us what sellers will offer for sale—35 million pounds per month. The difference, 20 million pounds of coffee per month, is called a surplus. More generally, a surplusThe amount by which the quantity supplied exceeds the quantity demanded at the current price. is the amount by which the quantity supplied exceeds the quantity demanded at the current price. There is, of course, no surplus at the equilibrium price; a surplus occurs only if the current price exceeds the equilibrium price.

Figure 3.8 A Surplus in the Market for Coffee

At a price of $8, the quantity supplied is 35 million pounds of coffee per month and the quantity demanded is 15 million pounds per month; there is a surplus of 20 million pounds of coffee per month. Given a surplus, the price will fall quickly toward the equilibrium level of $6.

A surplus in the market for coffee will not last long. With unsold coffee on the market, sellers will begin to reduce their prices to clear out unsold coffee. As the price of coffee begins to fall, the quantity of coffee supplied begins to decline. At the same time, the quantity of coffee demanded begins to rise. Remember that the reduction in quantity supplied is a movement along the supply curve—the curve itself does not shift in response to a reduction in price. Similarly, the increase in quantity demanded is a movement along the demand curve—the demand curve does not shift in response to a reduction in price. Price will continue to fall until it reaches its equilibrium level, at which the demand and supply curves intersect. At that point, there will be no tendency for price to fall further. In general, surpluses in the marketplace are short-lived. The prices of most goods and services adjust quickly, eliminating the surplus. Later on, we will discuss some markets in which adjustment of price to equilibrium may occur only very slowly or not at all.

Shortages

Just as a price above the equilibrium price will cause a surplus, a price below equilibrium will cause a shortage. A shortageThe amount by which the quantity demanded exceeds the quantity supplied at the current price. is the amount by which the quantity demanded exceeds the quantity supplied at the current price.

Figure 3.9 "A Shortage in the Market for Coffee" shows a shortage in the market for coffee. Suppose the price is $4 per pound. At that price, 15 million pounds of coffee would be supplied per month, and 35 million pounds would be demanded per month. When more coffee is demanded than supplied, there is a shortage.

Figure 3.9 A Shortage in the Market for Coffee

At a price of $4 per pound, the quantity of coffee demanded is 35 million pounds per month and the quantity supplied is 15 million pounds per month. The result is a shortage of 20 million pounds of coffee per month.

In the face of a shortage, sellers are likely to begin to raise their prices. As the price rises, there will be an increase in the quantity supplied (but not a change in supply) and a reduction in the quantity demanded (but not a change in demand) until the equilibrium price is achieved.

Shifts in Demand and Supply

Figure 3.10 Changes in Demand and Supply

A change in demand or in supply changes the equilibrium solution in the model. Panels (a) and (b) show an increase and a decrease in demand, respectively; Panels (c) and (d) show an increase and a decrease in supply, respectively.

A change in one of the variables (shifters) held constant in any model of demand and supply will create a change in demand or supply. A shift in a demand or supply curve changes the equilibrium price and equilibrium quantity for a good or service. Figure 3.10 "Changes in Demand and Supply" combines the information about changes in the demand and supply of coffee presented in Figure 3.2 "An Increase in Demand", Figure 3.3 "A Reduction in Demand", Figure 3.5 "An Increase in Supply", and Figure 3.6 "A Reduction in Supply" In each case, the original equilibrium price is $6 per pound, and the corresponding equilibrium quantity is 25 million pounds of coffee per month. Figure 3.10 "Changes in Demand and Supply" shows what happens with an increase in demand, a reduction in demand, an increase in supply, and a reduction in supply. We then look at what happens if both curves shift simultaneously. Each of these possibilities is discussed in turn below.

A Decrease in Supply

Panel (d) of Figure 3.10 "Changes in Demand and Supply" shows that a decrease in supply shifts the supply curve to the left. The equilibrium price rises to $7 per pound. As the price rises to the new equilibrium level, the quantity demanded decreases to 20 million pounds of coffee per month.

Possible supply shifters that could reduce supply include an increase in the prices of inputs used in the production of coffee, an increase in the returns available from alternative uses of these inputs, a decline in production because of problems in technology (perhaps caused by a restriction on pesticides used to protect coffee beans), a reduction in the number of coffee-producing firms, or a natural event, such as excessive rain.

Heads Up!

You are likely to be given problems in which you will have to shift a demand or supply curve.

Suppose you are told that an invasion of pod-crunching insects has gobbled up half the crop of fresh peas, and you are asked to use demand and supply analysis to predict what will happen to the price and quantity of peas demanded and supplied. Here are some suggestions.

Put the quantity of the good you are asked to analyze on the horizontal axis and its price on the vertical axis. Draw a downward-sloping line for demand and an upward-sloping line for supply. The initial equilibrium price is determined by the intersection of the two curves. Label the equilibrium solution. You may find it helpful to use a number for the equilibrium price instead of the letter “P.” Pick a price that seems plausible, say, 79¢ per pound. Do not worry about the precise positions of the demand and supply curves; you cannot be expected to know what they are.

Step 2 can be the most difficult step; the problem is to decide which curve to shift. The key is to remember the difference between a change in demand or supply and a change in quantity demanded or supplied. At each price, ask yourself whether the given event would change the quantity demanded. Would the fact that a bug has attacked the pea crop change the quantity demanded at a price of, say, 79¢ per pound? Clearly not; none of the demand shifters have changed. The event would, however, reduce the quantity supplied at this price, and the supply curve would shift to the left. There is a change in supply and a reduction in the quantity demanded. There is no change in demand.

Next check to see whether the result you have obtained makes sense. The graph in Step 2 makes sense; it shows price rising and quantity demanded falling.

It is easy to make a mistake such as the one shown in the third figure of this Heads Up! One might, for example, reason that when fewer peas are available, fewer will be demanded, and therefore the demand curve will shift to the left. This suggests the price of peas will fall—but that does not make sense. If only half as many fresh peas were available, their price would surely rise. The error here lies in confusing a change in quantity demanded with a change in demand. Yes, buyers will end up buying fewer peas. But no, they will not demand fewer peas at each price than before; the demand curve does not shift.

Simultaneous Shifts

As we have seen, when either the demand or the supply curve shifts, the results are unambiguous; that is, we know what will happen to both equilibrium price and equilibrium quantity, so long as we know whether demand or supply increased or decreased. However, in practice, several events may occur at around the same time that cause both the demand and supply curves to shift. To figure out what happens to equilibrium price and equilibrium quantity, we must know not only in which direction the demand and supply curves have shifted but also the relative amount by which each curve shifts. Of course, the demand and supply curves could shift in the same direction or in opposite directions, depending on the specific events causing them to shift.

For example, all three panels of Figure 3.11 "Simultaneous Decreases in Demand and Supply" show a decrease in demand for coffee (caused perhaps by a decrease in the price of a substitute good, such as tea) and a simultaneous decrease in the supply of coffee (caused perhaps by bad weather). Since reductions in demand and supply, considered separately, each cause the equilibrium quantity to fall, the impact of both curves shifting simultaneously to the left means that the new equilibrium quantity of coffee is less than the old equilibrium quantity. The effect on the equilibrium price, though, is ambiguous. Whether the equilibrium price is higher, lower, or unchanged depends on the extent to which each curve shifts.

Figure 3.11 Simultaneous Decreases in Demand and Supply

Both the demand and the supply of coffee decrease. Since decreases in demand and supply, considered separately, each cause equilibrium quantity to fall, the impact of both decreasing simultaneously means that a new equilibrium quantity of coffee must be less than the old equilibrium quantity. In Panel (a), the demand curve shifts farther to the left than does the supply curve, so equilibrium price falls. In Panel (b), the supply curve shifts farther to the left than does the demand curve, so the equilibrium price rises. In Panel (c), both curves shift to the left by the same amount, so equilibrium price stays the same.

If the demand curve shifts farther to the left than does the supply curve, as shown in Panel (a) of Figure 3.11 "Simultaneous Decreases in Demand and Supply", then the equilibrium price will be lower than it was before the curves shifted. In this case the new equilibrium price falls from $6 per pound to $5 per pound. If the shift to the left of the supply curve is greater than that of the demand curve, the equilibrium price will be higher than it was before, as shown in Panel (b). In this case, the new equilibrium price rises to $7 per pound. In Panel (c), since both curves shift to the left by the same amount, equilibrium price does not change; it remains $6 per pound.

Regardless of the scenario, changes in equilibrium price and equilibrium quantity resulting from two different events need to be considered separately. If both events cause equilibrium price or quantity to move in the same direction, then clearly price or quantity can be expected to move in that direction. If one event causes price or quantity to rise while the other causes it to fall, the extent by which each curve shifts is critical to figuring out what happens. Figure 3.12 "Simultaneous Shifts in Demand and Supply" summarizes what may happen to equilibrium price and quantity when demand and supply both shift.

Figure 3.12 Simultaneous Shifts in Demand and Supply

If simultaneous shifts in demand and supply cause equilibrium price or quantity to move in the same direction, then equilibrium price or quantity clearly moves in that direction. If the shift in one of the curves causes equilibrium price or quantity to rise while the shift in the other curve causes equilibrium price or quantity to fall, then the relative amount by which each curve shifts is critical to figuring out what happens to that variable.

As demand and supply curves shift, prices adjust to maintain a balance between the quantity of a good demanded and the quantity supplied. If prices did not adjust, this balance could not be maintained.

Notice that the demand and supply curves that we have examined in this chapter have all been drawn as linear. This simplification of the real world makes the graphs a bit easier to read without sacrificing the essential point: whether the curves are linear or nonlinear, demand curves are downward sloping and supply curves are generally upward sloping. As circumstances that shift the demand curve or the supply curve change, we can analyze what will happen to price and what will happen to quantity.

An Overview of Demand and Supply: The Circular Flow Model

Implicit in the concepts of demand and supply is a constant interaction and adjustment that economists illustrate with the circular flow model. The circular flow modelModel that provides a look at how markets work and how they are related to each other. provides a look at how markets work and how they are related to each other. It shows flows of spending and income through the economy.

A great deal of economic activity can be thought of as a process of exchange between households and firms. Firms supply goods and services to households. Households buy these goods and services from firms. Households supply factors of production—labor, capital, and natural resources—that firms require. The payments firms make in exchange for these factors represent the incomes households earn.

The flow of goods and services, factors of production, and the payments they generate is illustrated in Figure 3.13 "The Circular Flow of Economic Activity". This circular flow model of the economy shows the interaction of households and firms as they exchange goods and services and factors of production. For simplicity, the model here shows only the private domestic economy; it omits the government and foreign sectors.

Figure 3.13 The Circular Flow of Economic Activity

This simplified circular flow model shows flows of spending between households and firms through product and factor markets. The inner arrows show goods and services flowing from firms to households and factors of production flowing from households to firms. The outer flows show the payments for goods, services, and factors of production. These flows, in turn, represent millions of individual markets for products and factors of production.

The circular flow model shows that goods and services that households demand are supplied by firms in product marketsMarkets in which firms supply goods and services demanded by households.. The exchange for goods and services is shown in the top half of Figure 3.13 "The Circular Flow of Economic Activity". The bottom half of the exhibit illustrates the exchanges that take place in factor markets. factor marketsMarkets in which households supply factors of production—labor, capital, and natural resources—demanded by firms. are markets in which households supply factors of production—labor, capital, and natural resources—demanded by firms.

Our model is called a circular flow model because households use the income they receive from their supply of factors of production to buy goods and services from firms. Firms, in turn, use the payments they receive from households to pay for their factors of production.

The demand and supply model developed in this chapter gives us a basic tool for understanding what is happening in each of these product or factor markets and also allows us to see how these markets are interrelated. In Figure 3.13 "The Circular Flow of Economic Activity", markets for three goods and services that households want—blue jeans, haircuts, and apartments—create demands by firms for textile workers, barbers, and apartment buildings. The equilibrium of supply and demand in each market determines the price and quantity of that item. Moreover, a change in equilibrium in one market will affect equilibrium in related markets. For example, an increase in the demand for haircuts would lead to an increase in demand for barbers. Equilibrium price and quantity could rise in both markets. For some purposes, it will be adequate to simply look at a single market, whereas at other times we will want to look at what happens in related markets as well.

In either case, the model of demand and supply is one of the most widely used tools of economic analysis. That widespread use is no accident. The model yields results that are, in fact, broadly consistent with what we observe in the marketplace. Your mastery of this model will pay big dividends in your study of economics.

Case in Point: Demand, Supply, and Obesity

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Why are so many Americans fat? Put so crudely, the question may seem rude, but, indeed, the number of obese Americans has increased by more than 50% over the last generation, and obesity may now be the nation’s number one health problem. According to Sturm Roland in a recent RAND Corporation study, “Obesity appears to have a stronger association with the occurrence of chronic medical conditions, reduced physical health-related quality of life and increased health care and medication expenditures than smoking or problem drinking.”

Many explanations of rising obesity suggest higher demand for food. What more apt picture of our sedentary life style is there than spending the afternoon watching a ballgame on TV, while eating chips and salsa, followed by a dinner of a lavishly topped, take-out pizza? Higher income has also undoubtedly contributed to a rightward shift in the demand curve for food. Plus, any additional food intake translates into more weight increase because we spend so few calories preparing it, either directly or in the process of earning the income to buy it. A study by economists Darius Lakdawalla and Tomas Philipson suggests that about 60% of the recent growth in weight may be explained in this way—that is, demand has shifted to the right, leading to an increase in the equilibrium quantity of food consumed and, given our less strenuous life styles, even more weight gain than can be explained simply by the increased amount we are eating.

What accounts for the remaining 40% of the weight gain? Lakdawalla and Philipson further reason that a rightward shift in demand would by itself lead to an increase in the quantity of food as well as an increase in the price of food. The problem they have with this explanation is that over the post-World War II period, the relative price of food has declined by an average of 0.2 percentage points per year. They explain the fall in the price of food by arguing that agricultural innovation has led to a substantial rightward shift in the supply curve of food. As shown, lower food prices and a higher equilibrium quantity of food have resulted from simultaneous rightward shifts in demand and supply and that the rightward shift in the supply of food from S₁ to S₂ has been substantially larger than the rightward shift in the demand curve from D₁ to D₂.

Sources: Roland, Sturm, “The Effects of Obesity, Smoking, and Problem Drinking on Chronic Medical Problems and Health Care Costs,” Health Affairs, 2002; 21(2): 245–253. Lakdawalla, Darius and Tomas Philipson, “The Growth of Obesity and Technological Change: A Theoretical and Empirical Examination,” National Bureau of Economic Research Working Paper no. w8946, May 2002.

Answer to Try It! Problem

An increase in the price of movie theater tickets (a substitute for DVD rentals) will cause the demand curve for DVD rentals to shift to the right. An increase in the wages paid to DVD rental store clerks (an increase in the cost of a factor of production) shifts the supply curve to the left. Each event taken separately causes equilibrium price to rise. Whether equilibrium quantity will be higher or lower depends on which curve shifted more.

If the demand curve shifted more, then the equilibrium quantity of DVD rentals will rise [Panel (a)].

If the supply curve shifted more, then the equilibrium quantity of DVD rentals will fall [Panel (b)].

If the curves shifted by the same amount, then the equilibrium quantity of DVD rentals would not change [Panel (c)].

The Personal Computer Market

In the 1960s, to speak of computers was to speak of IBM, the dominant maker of large mainframe computers used by business and government agencies. Then between 1976, when Apple Computer introduced its first desktop computer, and 1981, when IBM produced its first personal computers (PCs), the computer usage expanded dramatically. Only 8.2% of U. S. households owned a personal computer in 1984. By 2003, 62% did. After that, the U.S. Census Bureau began asking only about Internet usage. By 2009, more than two-thirds of households had home Internet access. The tools of demand and supply tell the story from an economic perspective.

Technological change has been breathtakingly swift in the computer industry. Because personal computers have changed so dramatically in performance and in the range of the functions they perform, we shall speak of “quality-adjusted” personal computers. The price per unit of quality-adjusted desktop computers fell by about half every 50 months during the period 1976–1989. In the first half of the 1990s, those prices fell by half every 28 months. In the second half of the 1990s, the “halving time” fell to every 24 months.Ilkka Tuomi, “The Lives and Death of Moore’s Law.” http://www.firstmonday.org/issues/issue7_11/tuomi/index. First Monday (http://www.firstmonday.org) is a peer-reviewed journal on the Internet.

There are other indicators of the phenomenal change in computers. Between 1993 and 1998, the Bureau of Labor Statistics estimates that central processing unit (CPU) speed rose 1,263%, system memory increased 1,500%, hard drive capacity soared by 3,700%, and monitor size went up 13%. It seems safe to say that the dizzying pace of change recorded in the 1990s has increased in this century. A “computer” today is not the same good as a “computer” even five years ago. To make them comparable, we must adjust for changes in quality.

Initially, most personal computers were manufactured by Apple or Compaq; both companies were very profitable. The potential for profits attracted IBM and other firms to the industry. Unlike large mainframe computers, personal computer clones turned out to be fairly easy to manufacture. As shown in Table 4.1 "Personal Computer Shipments, Market Percentage Shares by Vendors, World and United States, 2011", the top six personal computer manufacturers produced only 43.3% of the personal computers sold in the world in 2011, and the largest manufacturer, Hewlett-Packard (HP), sold only about 17.5% of the total in that year. This is a far cry from the more than 90% of the mainframe computer market that IBM once held. The market has become far more competitive.

Figure 4.1 "The Personal Computer Market" illustrates changes that have occurred in the computer market. The horizontal axis shows the quantity of quality-adjusted personal computers. Thus, the quantity axis can be thought of as a unit of computing power. Similarly, the price axis shows the price per unit of computing power. The rapid increase in the number of firms, together with dramatic technological improvements, led to an increase in supply, shifting the supply curve in Figure 4.1 "The Personal Computer Market" to the right from S₁ to S₂.

Figure 4.1 The Personal Computer Market

The supply curve for quality-adjusted personal computers shifted markedly to the right, reducing the equilibrium price from P₁ to P₂ and increasing the equilibrium quantity from Q₁ to Q₂ in 2011.

Demand also shifted to the right from D₁ to D₂, as incomes rose and new uses for computers, from e-mail and social networking to Voice over Internet Protocol (VoIP) and Radio Frequency ID (RFID) tags (which allow wireless tracking of commercial shipments via desktop computers), altered the preferences of consumer and business users. Because we observe a fall in equilibrium price and an increase in equilibrium quantity, we conclude that the rightward shift in supply has outweighed the rightward shift in demand. The power of market forces has profoundly affected the way we live and work. One indication of the increasing importance of computers was that in August 2011, Exxon Mobil, an oil company that had been largest company in the United States in terms of the value of its outstanding stock, was the surpassed by Apple Computer Inc., whose value reached $350 billion.

The Markets for Crude Oil and for Gasoline

The market for crude oil took a radical turn in 1973. The price per barrel of crude oil quadrupled between 1973 and 1974. Price remained high until the early 1980s but fell back drastically and remained low for about two decades. In 2004, the price of oil began to move upward and by 2008 had reached $147 per barrel.

What caused the dramatic increase in gasoline and oil prices in 2008? It appeared to be increasing worldwide demand outpacing producers’ ability—or willingness—to increase production much. This increase in demand is illustrated in Figure 4.2 "Increasing Demand for Crude Oil".

Figure 4.2 Increasing Demand for Crude Oil

The price of oil was $35 per barrel at the beginning of 2004, as determined by the intersection of world demand, D₁, and world supply, S₁. Increasing world demand, prompted largely by increasing demand from China as well as from other countries, shifted world demand to D₂, pushing the price as high as $140 per barrel by the middle of 2008.

Higher oil prices also increase the cost of producing virtually every good or service since the production of most goods requires transportation. These costs inevitably translate into higher prices for nearly all goods and services. Supply curves of the goods and services thus affected shift to the left, putting downward pressure on output and upward pressure on prices.

Graphically, the impact of higher gasoline prices on businesses that use gasoline is illustrated in Figure 4.3 "The Impact of Higher Gasoline Prices". Because higher gasoline prices increase the cost of doing business, they shift the supply curves for nearly all businesses to the left, putting upward pressure on prices and downward pressure on output. In the case shown here, the supply curve in a typical industry shifts from S₁ to S₂. This increases the equilibrium price from P₁ to P₂ and reduces the equilibrium quantity from Q₁ to Q₂.

Figure 4.3 The Impact of Higher Gasoline Prices

Higher gasoline prices increase the cost of producing virtually every good or service. In the case shown here, the supply curve in a typical industry shifts from S₁ to S₂. This increases the equilibrium price from P₁ to P₂ and reduces equilibrium quantity from Q₁ to Q₂.

As the world economy slowed dramatically in the second half of 2008, the demand curve for oil shifted to the left. By November 2008, the price per barrel had dropped to below $60 per barrel. As gas prices also subsided, so did the threat of higher prices in other industries.

The Stock Market

The circular flow model suggests that capital, like other factors of production, is supplied by households to firms. Firms, in turn, pay income to those households for the use of their capital. Generally speaking, however, capital is actually owned by firms themselves. General Motors owns its assembly plants, and Wal-Mart owns its stores; these firms therefore own their capital. But firms, in turn, are owned by people—and those people, of course, live in households. It is through their ownership of firms that households own capital.

A firm may be owned by one individual (a sole proprietorshipA firm owned by one individual.), by several individuals (a partnershipA firm owned by several individuals.), or by shareholders who own stock in the firm (a corporationA firm owned by shareholders who own stock in the firm.). Although most firms in the United States are sole proprietorships or partnerships, the bulk of the nation’s total output (about 90%) is produced by corporations. Corporations also own most of the capital (machines, plants, buildings, and the like).

This section describes how the prices of shares of corporate stockShares in the ownership of a corporation., shares in the ownership of a corporation, are determined by the interaction of demand and supply. Ultimately, the same forces that determine the value of a firm’s stock determine the value of a sole proprietorship or partnership.

When a corporation needs funds to increase its capital or for other reasons, one means at its disposal is to issue new stock in the corporation. (Other means include borrowing funds or using past profits.) Once the new shares have been sold in what is called an initial public offering (IPO), the corporation receives no further funding as shares of its stock are bought and sold on the secondary market. The secondary market is the market for stocks that have been issued in the past, and the daily news reports about stock prices almost always refer to activity in the secondary market. Generally, the corporations whose shares are traded are not involved in these transactions.

The stock marketThe set of institutions in which shares of stock are bought and sold. is the set of institutions in which shares of stock are bought and sold. The New York Stock Exchange (NYSE) is one such institution. There are many others all over the world, such as the DAX in Germany and the Bolsa in Mexico. To buy or sell a share of stock, one places an order with a stockbroker who relays the order to one of the traders at the NYSE or at some other exchange.

The process through which shares of stock are bought and sold can seem chaotic. At many exchanges, traders with orders from customers who want to buy stock shout out the prices those customers are willing to pay. Traders with orders from customers who want to sell shout out offers of prices at which their customers are willing to sell. Some exchanges use electronic trading, but the principle is the same: if the price someone is willing to pay matches the price at which someone else is willing to sell, the trade is made. The most recent price at which a stock has traded is reported almost instantaneously throughout the world.

Figure 4.4 "Demand and Supply in the Stock Market" applies the model of demand and supply to the determination of stock prices. Suppose the demand curve for shares in Intel Corporation is given by D₁ and the supply by S₁. (Even though the total number of shares outstanding is fixed at any point in time, the supply curve is not vertical. Rather, the supply curve is upward sloping because it represents how many shares current owners are prepared to sell at each price, and that number will be greater at higher prices.) Suppose that these curves intersect at a price of $25, at which Q₁ shares are traded each day. If the price were higher, more shares would be offered for sale than would be demanded, and the price would quickly fall. If the price were lower, more shares would be demanded than would be supplied, and the price would quickly rise. In general, we can expect the prices of shares of stock to move quickly to their equilibrium levels.

Figure 4.4 Demand and Supply in the Stock Market

The equilibrium price of stock shares in Intel Corporation is initially $25, determined by the intersection of demand and supply curves D₁ and S₁, at which Q₁ million shares are traded each day.

The intersection of the demand and supply curves for shares of stock in a particular company determines the equilibrium price for a share of stock. But what determines the demand and supply for shares of a company’s stock?

The owner of a share of a company’s stock owns a share of the company, and, hence, a share of its profits; typically, a corporation will retain and reinvest some of its profits to increase its future profitability. The profits kept by a company are called retained earningsProfits kept by a company.. Profits distributed to shareholders are called dividendsProfits distributed to shareholders.. Because a share of stock gives its owner a claim on part of a company’s future profits, it follows that the expected level of future profits plays a role in determining the value of its stock.

Of course, those future profits cannot be known with certainty; investors can only predict what they might be, based on information about future demand for the company’s products, future costs of production, information about the soundness of a company’s management, and so on. Stock prices in the real world thus reflect estimates of a company’s profits projected into the future.

The downward slope of the demand curve suggests that at lower prices for the stock, more people calculate that the firm’s future earnings will justify the stock’s purchase. The upward slope of the supply curve tells us that as the price of the stock rises, more people conclude that the firm’s future earnings do not justify holding the stock and therefore offer to sell it. At the equilibrium price, the number of shares supplied by people who think holding the stock no longer makes sense just balances the number of shares demanded by people who think it does.

What factors, then, cause the demand or supply curves for shares of stocks to shift? The most important factor is a change in the expectations of a company’s future profits. Suppose Intel announces a new generation of computer chips that will lead to faster computers with larger memories. Current owners of Intel stock would adjust upward their estimates of what the value of a share of Intel stock should be. At the old equilibrium price of $25 fewer owners of Intel stock would be willing to sell. Since this would be true at every possible share price, the supply curve for Intel stock would shift to the left, as shown in Figure 4.5 "A Change in Expectations Affects the Price of Corporate Stock". Just as the expectation that a company will be more profitable shifts the supply curve for its stock to the left, that same change in expectations will cause more people to want to purchase the stock, shifting the demand curve to the right. In Figure 4.5 "A Change in Expectations Affects the Price of Corporate Stock", we see the supply curve shifting to the left, from S₁ to S₂, while the demand curve shifts to the right, from D₁ to D₂.

Figure 4.5 A Change in Expectations Affects the Price of Corporate Stock

If financial investors decide that a company is likely to be more profitable, then the supply of the stock shifts to the left (in this case, from S₁ to S₂), and the demand for the stock shifts to the right (in this case, from D₁ to D₂), resulting in an increase in price from P₁ to P₂.

Other factors may alter the price of an individual corporation’s share of stock or the level of stock prices in general. For example, demographic change and rising incomes have affected the demand for stocks in recent years. For example, with a large proportion of the U.S. population nearing retirement age and beginning to think about and plan for their lives during retirement, the demand for stocks has risen.

Information on the economy as a whole is also likely to affect stock prices. If the economy overall is doing well and people expect that to continue, they may become more optimistic about how profitable companies will be in general, and thus the prices of stocks will rise. Conversely, expectations of a sluggish economy, as happened in the fall of 2008, could cause stock prices in general to fall.

The stock market is bombarded with new information every minute of every day. Firms announce their profits of the previous quarter. They announce that they plan to move into a new product line or sell their goods in another country. We learn that the price of Company A’s good, which is a substitute for one sold by Company B, has risen. We learn that countries sign trade agreements, launch wars, or make peace. All of this information may affect stock prices because any information can affect how buyers and sellers value companies.

Case in Point: The Great Recession, the Arab Spring, and the Oil Market

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Oil markets have been on a roller coaster ride for the last few years. Even after the official start of the recession in the United States in December 2007, oil prices continued to climb, peaking in the summer of 2008 at over $130 per barrel. Although demand in the United States and Europe was already weakening, growth in the rest of the world, particularly in China and India, was still strong. Overall, demand was rising.

Oil prices dropped precipitously following the start of the financial crisis and the deepening of the recession in the fall of 2008. Within a few months, the price of oil had dropped to around $40 and was in the $70 to $80 range for much of the rest of 2009 and the first half of 2010.

The so-called Arab Spring actually began with demonstrations late in 2010 in Tunisia. They quickly spread to Egypt, Bahrain, Syria, Yemen, Algeria, Jordan, Morocco, and Yemen. There were demonstrations in Saudi Arabia, Kuwait, Lebanon, Mauritania, and Sudan. By the fall of 2011, the movement had toppled the regimes of Zine El Abidine Ben Ali in Tunisia, Hosni Mubarak in Egypt, and Muammar al-Gaddafi in Libya.

The movement had a large impact on oil prices as it raised questions about the security of oil supplies. The supply curve of oil shifted to the left, forcing the price upward. Not only were several key suppliers of oil affected, but at times the ability to transport oil through the Suez Canal was affected.

Oil prices rose to well over $100 per barrel by early 2011. They then began to subside again as some of the uprisings were subdued or ending, especially in the oil-rich Gulf countries. By the fall of 2011, oil prices had fallen about 20% as compared to earlier in the year.

Answer to Try It! Problem

The information given in the problem suggests that the airline’s profits are likely to fall below expectations. Current owners of the airline’s stock and potential buyers of the stock would adjust downward their estimates of what the value of the corporation’s stock should be. As a result the supply curve for the stock would increase, shifting it to the right, while the demand curve for the stock would decrease, shifting it to the left. As a result, equilibrium price of the stock falls from P₁ to P₂. What happens to equilibrium quantity depends on the extent to which each curve shifts. In the diagram, equilibrium quantity is shown to decrease from Q₁ to Q₂.

Agricultural Price Floors

Governments often seek to assist farmers by setting price floors in agricultural markets. A minimum allowable price set above the equilibrium price is a price floorA minimum allowable price set above the equilibrium price.. With a price floor, the government forbids a price below the minimum. (Notice that, if the price floor were for whatever reason set below the equilibrium price, it would be irrelevant to the determination of the price in the market since nothing would prohibit the price from rising to equilibrium.) A price floor that is set above the equilibrium price creates a surplus.

Figure 4.6 "Price Floors in Wheat Markets" shows the market for wheat. Suppose the government sets the price of wheat at P_F. Notice that P_F is above the equilibrium price of P_E. At P_F, we read over to the demand curve to find that the quantity of wheat that buyers will be willing and able to purchase is W₁ bushels. Reading over to the supply curve, we find that sellers will offer W₂ bushels of wheat at the price floor of P_F. Because P_F is above the equilibrium price, there is a surplus of wheat equal to (W₂ − W₁) bushels. The surplus persists because the government does not allow the price to fall.

Figure 4.6 Price Floors in Wheat Markets

A price floor for wheat creates a surplus of wheat equal to (W₂ - W₁) bushels.

Why have many governments around the world set price floors in agricultural markets? Farming has changed dramatically over the past two centuries. Technological improvements in the form of new equipment, fertilizers, pesticides, and new varieties of crops have led to dramatic increases in crop output per acre. Worldwide production capacity has expanded markedly. As we have learned, technological improvements cause the supply curve to shift to the right, reducing the price of food. While such price reductions have been celebrated in computer markets, farmers have successfully lobbied for government programs aimed at keeping their prices from falling.

While the supply curve for agricultural goods has shifted to the right, the demand has increased with rising population and with rising income. But as incomes rise, people spend a smaller and smaller fraction of their incomes on food. While the demand for food has increased, that increase has not been nearly as great as the increase in supply. Figure 4.7 "Supply and Demand Shifts for Agricultural Products" shows that the supply curve has shifted much farther to the right, from S₁ to S₂, than the demand curve has, from D₁ to D₂. As a result, equilibrium quantity has risen dramatically, from Q₁ to Q₂, and equilibrium price has fallen, from P₁ to P₂.

On top of this long-term historical trend in agriculture, agricultural prices are subject to wide swings over shorter periods. Droughts or freezes can sharply reduce supplies of particular crops, causing sudden increases in prices. Demand for agricultural goods of one country can suddenly dry up if the government of another country imposes trade restrictions against its products, and prices can fall. Such dramatic shifts in prices and quantities make incomes of farmers unstable.

Figure 4.7 Supply and Demand Shifts for Agricultural Products

A relatively large increase in the supply of agricultural products, accompanied by a relatively small increase in demand, has reduced the price received by farmers and increased the quantity of agricultural goods.

The Great Depression of the 1930s led to a major federal role in agriculture. The Depression affected the entire economy, but it hit farmers particularly hard. Prices received by farmers plunged nearly two-thirds from 1930 to 1933. Many farmers had a tough time keeping up mortgage payments. By 1932, more than half of all farm loans were in default.

Farm legislation passed during the Great Depression has been modified many times, but the federal government has continued its direct involvement in agricultural markets. This has meant a variety of government programs that guarantee a minimum price for some types of agricultural products. These programs have been accompanied by government purchases of any surplus, by requirements to restrict acreage in order to limit those surpluses, by crop or production restrictions, and the like.

To see how such policies work, look back at Figure 4.6 "Price Floors in Wheat Markets". At P_F, W₂ bushels of wheat will be supplied. With that much wheat on the market, there is market pressure on the price of wheat to fall. To prevent price from falling, the government buys the surplus of (W₂ - W₁) bushels of wheat, so that only W₁ bushels are actually available to private consumers for purchase on the market. The government can store the surpluses or find special uses for them. For example, surpluses generated in the United States have been shipped to developing countries as grants-in-aid or distributed to local school lunch programs. As a variation on this program, the government can require farmers who want to participate in the price support program to reduce acreage in order to limit the size of the surpluses.

After 1973, the government stopped buying the surpluses (with some exceptions) and simply guaranteed farmers a “target price.” If the average market price for a crop fell below the crop’s target price, the government paid the difference. If, for example, a crop had a market price of $3 per unit and a target price of $4 per unit, the government would give farmers a payment of $1 for each unit sold. Farmers would thus receive the market price of $3 plus a government payment of $1 per unit. For farmers to receive these payments, they had to agree to remove acres from production and to comply with certain conservation provisions. These restrictions sought to reduce the size of the surplus generated by the target price, which acted as a kind of price floor.

What are the effects of such farm support programs? The intention is to boost and stabilize farm incomes. But, with price floors, consumers pay more for food than they would otherwise, and governments spend heavily to finance the programs. With the target price approach, consumers pay less, but government financing of the program continues. U.S. federal spending for agriculture averaged well over $22 billion per year between 2003 and 2007, roughly $70 per person.

Help to farmers has sometimes been justified on the grounds that it boosts incomes of “small” farmers. However, since farm aid has generally been allotted on the basis of how much farms produce rather than on a per-farm basis, most federal farm support has gone to the largest farms. If the goal is to eliminate poverty among farmers, farm aid could be redesigned to supplement the incomes of small or poor farmers rather than to undermine the functioning of agricultural markets.

In 1996, the U.S. Congress passed the Federal Agriculture Improvement and Reform Act of 1996, or FAIR. The thrust of the new legislation was to do away with the various programs of price support for most crops and hence provide incentives for farmers to respond to market price signals. To protect farmers through a transition period, the act provided for continued payments that were scheduled to decline over a seven-year period. However, with prices for many crops falling in 1998, the U.S. Congress passed an emergency aid package that increased payments to farmers. In 2008, as farm prices reached record highs, Congress passed a farm bill that increased subsidy payments to $40 billion. It did, however, for the first time limit payments to the wealthiest farmers. Individual farmers whose farm incomes exceed $750,000 (or $1.5 million for couples) would be ineligible for some subsidy programs.

Rental Price Ceilings

The purpose of rent control is to make rental units cheaper for tenants than they would otherwise be. Unlike agricultural price controls, rent control in the United States has been largely a local phenomenon, although there were national rent controls in effect during World War II. Currently, about 200 cities and counties have some type of rent control provisions, and about 10% of rental units in the United States are now subject to price controls. New York City’s rent control program, which began in 1943, is among the oldest in the country. Many other cities in the United States adopted some form of rent control in the 1970s. Rent controls have been pervasive in Europe since World War I, and many large cities in poorer countries have also adopted rent controls.

Rent controls in different cities differ in terms of their flexibility. Some cities allow rent increases for specified reasons, such as to make improvements in apartments or to allow rents to keep pace with price increases elsewhere in the economy. Often, rental housing constructed after the imposition of the rent control ordinances is exempted. Apartments that are vacated may also be decontrolled. For simplicity, the model presented here assumes that apartment rents are controlled at a price that does not change.

Figure 4.8 Effect of a Price Ceiling on the Market for Apartments

A price ceiling on apartment rents that is set below the equilibrium rent creates a shortage of apartments equal to (A₂ − A₁) apartments.

Figure 4.8 "Effect of a Price Ceiling on the Market for Apartments" shows the market for rental apartments. Notice that the demand and supply curves are drawn to look like all the other demand and supply curves you have encountered so far in this text: the demand curve is downward-sloping and the supply curve is upward-sloping.

The demand curve shows that a higher price (rent) reduces the quantity of apartments demanded. For example, with higher rents, more young people will choose to live at home with their parents. With lower rents, more will choose to live in apartments. Higher rents may encourage more apartment sharing; lower rents would induce more people to live alone.

The supply curve is drawn to show that as rent increases, property owners will be encouraged to offer more apartments to rent. Even though an aerial photograph of a city would show apartments to be fixed at a point in time, owners of those properties will decide how many to rent depending on the amount of rent they anticipate. Higher rents may also induce some homeowners to rent out apartment space. In addition, renting out apartments implies a certain level of service to renters, so that low rents may lead some property owners to keep some apartments vacant.

Rent control is an example of a price ceilingA maximum allowable price., a maximum allowable price. With a price ceiling, the government forbids a price above the maximum. A price ceiling that is set below the equilibrium price creates a shortage that will persist.

Suppose the government sets the price of an apartment at P_C in Figure 4.8 "Effect of a Price Ceiling on the Market for Apartments". Notice that P_C is below the equilibrium price of P_E. At P_C, we read over to the supply curve to find that sellers are willing to offer A₁ apartments. Reading over to the demand curve, we find that consumers would like to rent A₂ apartments at the price ceiling of P_C. Because P_C is below the equilibrium price, there is a shortage of apartments equal to (A₂ - A₁). (Notice that if the price ceiling were set above the equilibrium price it would have no effect on the market since the law would not prohibit the price from settling at an equilibrium price that is lower than the price ceiling.)

Figure 4.9 The Unintended Consequences of Rent Control

Controlling apartment rents at P_C creates a shortage of (A₂ − A₁) apartments. For A₁ apartments, consumers are willing and able to pay P_B, which leads to various “backdoor” payments to apartment owners.

If rent control creates a shortage of apartments, why do some citizens nonetheless clamor for rent control and why do governments often give in to the demands? The reason generally given for rent control is to keep apartments affordable for low- and middle-income tenants.

But the reduced quantity of apartments supplied must be rationed in some way, since, at the price ceiling, the quantity demanded would exceed the quantity supplied. Current occupants may be reluctant to leave their dwellings because finding other apartments will be difficult. As apartments do become available, there will be a line of potential renters waiting to fill them, any of whom is willing to pay the controlled price of P_C or more. In fact, reading up to the demand curve in Figure 4.9 "The Unintended Consequences of Rent Control" from A₁ apartments, the quantity available at P_C, you can see that for A₁ apartments, there are potential renters willing and able to pay P_B. This often leads to various “backdoor” payments to apartment owners, such as large security deposits, payments for things renters may not want (such as furniture), so-called “key” payments (“The monthly rent is $500 and the key price is $3,000”), or simple bribes.

In the end, rent controls and other price ceilings often end up hurting some of the people they are intended to help. Many people will have trouble finding apartments to rent. Ironically, some of those who do find apartments may actually end up paying more than they would have paid in the absence of rent control. And many of the people that the rent controls do help (primarily current occupants, regardless of their income, and those lucky enough to find apartments) are not those they are intended to help (the poor). There are also costs in government administration and enforcement.

Because New York City has the longest history of rent controls of any city in the United States, its program has been widely studied. There is general agreement that the rent control program has reduced tenant mobility, led to a substantial gap between rents on controlled and uncontrolled units, and favored long-term residents at the expense of newcomers to the city.Richard Arnott, “Time for Revisionism on Rent Control,” Journal of Economic Perspectives 9(1) (Winter, 1995): 99–120. These distortions have grown over time, another frequent consequence of price controls.

A more direct means of helping poor tenants, one that would avoid interfering with the functioning of the market, would be to subsidize their incomes. As with price floors, interfering with the market mechanism may solve one problem, but it creates many others at the same time.

Case in Point: Corn: It Is Not Just Food Any More

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Government support for corn dates back to the Agricultural Act of 1938 and, in one form or another, has been part of agricultural legislation ever since. Types of supports have ranged from government purchases of surpluses to target pricing, land set asides, and loan guarantees. According to one estimate, the U.S. government spent nearly $42 billion to support corn between 1995 and 2004.

Then, during the period of rising oil prices of the late 1970s and mounting concerns about dependence on foreign oil from volatile regions in the world, support for corn, not as a food, but rather as an input into the production of ethanol—an alternative to oil-based fuel—began. Ethanol tax credits were part of the Energy Act of 1978. Since 1980, a tariff of 50¢ per gallon against imported ethanol, even higher today, has served to protect domestic corn-based ethanol from imported ethanol, in particular from sugar-cane-based ethanol from Brazil.

The Energy Policy Act of 2005 was another milestone in ethanol legislation. Through loan guarantees, support for research and development, and tax credits, it mandated that 4 billion gallons of ethanol be used by 2006 and 7.5 billion gallons by 2012. Ethanol production had already reached 6.5 billion gallons by 2007, so new legislation in 2007 upped the ante to 15 billion gallons by 2015.

Beyond the increased amount the government is spending to support corn and corn-based ethanol, criticism of the policy has three major prongs:

1. Corn-based ethanol does little to reduce U.S. dependence on foreign oil because the energy required to produce a gallon of corn-based ethanol is quite high. A 2006 National Academy of Sciences paper estimated that one gallon of ethanol is needed to bring 1.25 gallons of it to market. Other studies show an even less favorable ratio.
2. Biofuels, such as corn-based ethanol, are having detrimental effects on the environment, with increased deforestation, stemming from more land being used to grow fuel inputs, contributing to global warming.
3. The diversion of corn and other crops from food to fuel is contributing to rising food prices and an increase in world hunger. C. Ford Runge and Benjamin Senauer wrote in Foreign Affairs that even small increases in prices of food staples have severe consequences on the very poor of the world, and “Filling the 25-gallon tank of an SUV with pure ethanol requires over 450 pounds of corn—which contains enough calories to feed one person for a year.”

Some of these criticisms may be contested as exaggerated: Will the ratio of energy-in to energy-out improve as new technologies emerge for producing ethanol? Did not other factors, such as weather and rising food demand worldwide, contribute to higher grain prices? Nonetheless, it is clear that corn-based ethanol is no free lunch. It is also clear that the end of government support for corn is nowhere to be seen.

Sources: Alexei Barrionuevo, “Mountains of Corn and a Sea of Farm Subsidies,” New York Times, November 9, 2005, online version; David Freddoso, “Children of the Corn,” National Review Online, May 6, 2008; C. Ford Runge and Benjamin Senauer, “How Biofuels Could Starve the Poor,” Foreign Affairs, May/June 2007, online version; Michael Grunwald, “The Clean Energy Scam,” Time 171:14 (April 7, 2008): 40–45.

Answer to Try It! Problem

A minimum wage (W_min) that is set above the equilibrium wage would create a surplus of unskilled labor equal to (L₂ - L₁). That is, L₂ units of unskilled labor are offered at the minimum wage, but companies only want to use L₁ units at that wage. Because unskilled workers are a substitute for a skilled workers, forcing the price of unskilled workers higher would increase the demand for skilled labor and thus increase their wages.

The Demand and Supply for Health Care

Figure 4.11 Total Spending for Physician Office Visits

Total spending on physician office visits is $30 per visit multiplied by 1,000,000 visits per week, which equals $30,000,000. It is the shaded area bounded by price and quantity.

When we speak of “health care,” we are speaking of the entire health-care industry. This industry produces services ranging from heart transplant operations to therapeutic massages; it produces goods ranging from X-ray machines to aspirin tablets. Clearly each of these goods and services is exchanged in a particular market. To assess the market forces affecting health care, we will focus first on just one of these markets: the market for physician office visits. When you go to the doctor, you are part of the demand for these visits. Your doctor, by seeing you, is part of the supply.

Figure 4.11 "Total Spending for Physician Office Visits" shows the market, assuming that it operates in a fashion similar to other markets. The demand curve D₁ and the supply curve S₁ intersect at point E, with an equilibrium price of $30 per office visit. The equilibrium quantity of office visits per week is 1,000,000.

We can use the demand and supply graph to show total spending, which equals the price per unit (in this case, $30 per visit) times the quantity consumed (in this case, 1,000,000 visits per week). Total spending for physician office visits thus equals $30,000,000 per week ($30 times 1,000,000 visits). We show total spending as the area of a rectangle bounded by the price and the quantity. It is the shaded region in Figure 4.11 "Total Spending for Physician Office Visits".

The picture in Figure 4.11 "Total Spending for Physician Office Visits" misses a crucial feature of the market. Most people in the United States have health insurance, provided either by private firms, by private purchases, or by the government. With health insurance, people agree to pay a fixed amount to the insurer in exchange for the insurer’s agreement to pay for most of the health-care expenses they incur. While insurance plans differ in their specific provisions, let us suppose that all individuals have plans that require them to pay $10 for an office visit; the insurance company will pay the rest.

How will this insurance affect the market for physician office visits? If it costs only $10 for a visit instead of $30, people will visit their doctors more often. The quantity of office visits demanded will increase. In Figure 4.12 "Total Spending for Physician Office Visits Covered by Insurance", this is shown as a movement along the demand curve. Think about your own choices. When you get a cold, do you go to the doctor? Probably not, if it is a minor cold. But if you feel like you are dying, or wish you were, you probably head for the doctor. Clearly, there are lots of colds in between these two extremes. Whether you drag yourself to the doctor will depend on the severity of your cold and what you will pay for a visit. At a lower price, you are more likely to go to the doctor; at a higher price, you are less likely to go.

In the case shown, the quantity of office visits rises to 1,500,000 per week. But that suggests a potential problem. The quantity of visits supplied at a price of $30 per visit was 1,000,000. According to supply curve S₁, it will take a price of $50 per visit to increase the quantity supplied to 1,500,000 visits (Point F on S₁). But consumers—patients—pay only $10.

Insurers make up the difference between the fees doctors receive and the price patients pay. In our example, insurers pay $40 per visit of insured patients to supplement the $10 that patients pay. When an agent other than the seller or the buyer pays part of the price of a good or service, we say that the agent is a third-party payerAn agent other than the seller or the buyer who pays part of the price of a good or service..

Notice how the presence of a third-party payer affects total spending on office visits. When people paid for their own visits, and the price equaled $30 per visit, total spending equaled $30 million per week. Now doctors receive $50 per visit and provide 1,500,000 visits per week. Total spending has risen to $75 million per week ($50 times 1,500,000 visits, shown by the darkly shaded region plus the lightly shaded region).

Figure 4.12 Total Spending for Physician Office Visits Covered by Insurance

With insurance, the quantity of physician office visits demanded rises to 1,500,000. The supply curve shows that it takes a price of $50 per visit to increase the quantity supplied to 1,500,000 visits. Patients pay $10 per visit and insurance pays $40 per visit. Total spending rises to $75,000,000 per week, shown by the darkly shaded region plus the lightly shaded region.

The response described in Figure 4.12 "Total Spending for Physician Office Visits Covered by Insurance" holds for many different types of goods and services covered by insurance or otherwise paid for by third-party payers. For example, the availability of scholarships and subsidized tuition at public and private universities increases the quantity of education demanded and the total expenditures on higher education. In markets with third-party payers, an equilibrium is achieved, but it is not at the intersection of the demand and supply curves. The effect of third-party payers is to decrease the price that consumers directly pay for the goods and services they consume and to increase the price that suppliers receive. Consumers use more than they would in the absence of third-party payers, and providers are encouraged to supply more than they otherwise would. The result is increased total spending.

Case in Point: The Oregon Plan

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The health-care industry presents us with a dilemma. Clearly, it makes sense for people to have health insurance. Just as clearly, health insurance generates a substantial increase in spending for health care. If that spending is to be limited, some mechanism must be chosen to do it. One mechanism would be to require patients to pay a larger share of their own health-care consumption directly, reducing the payments made by third-party payers. Allowing people to accumulate tax-free private medical savings accounts is one way to do this. Another option is to continue the current trend to use insurance companies as the agents that limit spending. A third option is government regulation; this Case in Point describes how the state of Oregon tried to limit health-care spending by essentially refusing to be a third-party payer for certain services.

Like all other states, Oregon has wrestled with the problem of soaring Medicaid costs. Its solution to the problem illustrates some of the choices society might make in seeking to reduce health-care costs.

Oregon used to have a plan similar to plans in many other states. Households whose incomes were lower than 50% of the poverty line qualified for Medicaid. In 1987, the state began an effort to manage its Medicaid costs. It decided that it would no longer fund organ transplants and that it would use the money saved to give better care to pregnant women. The decision turned out to be a painful one; the first year, a seven-year-old boy with leukemia, who might have been saved with a bone marrow transplant, died. But state officials argued that the shift of expenditures to pregnant women would ultimately save more lives.

The state gradually expanded its concept of determining what services to fund and what services not to fund. It collapsed a list of 10,000 different diagnoses that had been submitted to its Medicaid program in the past into a list of more than 700 condition-treatment pairs. One such pair, for example, is appendicitis-appendectomy. Health-care officials then ranked these pairs in order of priority. The rankings were based on such factors as the seriousness of a particular condition and the cost and efficacy of treatments. The state announced that it would provide Medicaid to all households below the poverty line, but that it would not fund any procedure ranked below a certain level, initially number 588 on its list. The plan also set a budget limit for any one year; if spending rose above that limit, the legislature must appropriate additional money or drop additional procedures from the list of those covered by the plan. The Oregon Health Plan officially began operation in 1994.

While the Oregon plan has been applied only to households below the poverty line that are not covered by other programs, it suggests a means of reducing health-care spending. Clearly, if part of the health-care problem is excessive provision of services, a system designed to cut services must determine what treatments not to fund.

Professors Jonathan Oberlander, Theodore Marmor, and Lawrence Jacobs studied the impact of this plan in practice through the year 2000 and found that, in contrast to initial expectations, excluded procedures were generally ones of marginal medical value, so the “line in the sand” had little practical significance. In addition, they found that patients were often able to receive supposedly excluded services when physicians, for example, treated an uncovered illness in conjunction with a covered one. During the period of the study, the number of people covered by the plan expanded substantially and yet rationing of services essentially did not occur. How do they explain this seeming contradiction? Quite simply: state government increased revenues from various sources to support the plan. Indeed, they argue that, because treatments that might not be included were explicitly stated, political pressure made excluding them even more difficult and may have inadvertently increased the cost of the program.

In the early 2000s, Oregon, like many other states, confronted severe budgetary pressures. To limit spending, it chose the perhaps less visible strategy of reducing the number of people covered through the plan. Once serving more than 100,000 people, budget cuts reduced the number served to about 17,000. Whereas in 1996, 11% of Oregonians lacked health insurance, in 2008 16% did.

Trailblazing again, in 2008 Oregon realized that its budget allowed room for coverage for a few thousand additional people. But how to choose among the 130,000 eligibles? The solution: to hold a lottery. More than 90,000 people queued up, hoping to be lucky winners.

Sources: Jonathan Oberlander, Theodore Marmor, and Lawrence Jacobs, “Rationing Medical Care: Rhetoric and Reality in the Oregon Health Plan,” Canadian Medical Association Journal 164: 11 (May 29, 2001): 1583–1587; William Yardley, “Drawing Lots for Health Care,” The New York Times, March 13, 2008: p. A12.

Answer to Try It! Problem

Without a third-party payer for education, the graph shows equilibrium tuition of P₁ and equilibrium quantity of education of Q₁. State support for education lowers tuition that students pay to P₂. As a result, students demand Q₂ courses per year. To provide that amount of education, educational institutions require tuition per course of P₃. Without a third-party payer, spending on education is 0P₁EQ₁. With a third-party payer, spending rises to 0P₃FQ₂.

Phases of the Business Cycle

Figure 5.1 "Phases of the Business Cycle" shows a stylized picture of a typical business cycle. It shows that economies go through periods of increasing and decreasing real GDP, but that over time they generally move in the direction of increasing levels of real GDP. A sustained period in which real GDP is rising is an expansionA sustained period in which real GDP is rising.; a sustained period in which real GDP is falling is a recessionA sustained period in which real GDP is falling.. Typically, an economy is said to be in a recession when real GDP drops for two consecutive quarters, but in the United States, the responsibility of defining precisely when the economy is in recession is left to the Business Cycle Dating Committee of the National Bureau of Economic Research (NBER). The committee defines a recession as a “significant decline in economic activity spread across the economy, lasting more than a few months, normally visible in real GDP, real income, employment, industrial production, and wholesale-retail sales.”“The NBER’s Recession Dating Procedure,” National Bureau of Economic Research, January 7, 2008.

Figure 5.1 Phases of the Business Cycle

The business cycle is a series of expansions and contractions in real GDP. The cycle begins at a peak and continues through a recession, a trough, and an expansion. A new cycle begins at the next peak. Here, the first peak occurs at time t₁, the trough at time t₂, and the next peak at time t₃. Notice that there is a tendency for real GDP to rise over time.

At time t₁ in Figure 5.1 "Phases of the Business Cycle", an expansion ends and real GDP turns downward. The point at which an expansion ends and a recession begins is called the peakThe point of the business cycle at which an expansion ends and a recession begins. of the business cycle. Real GDP then falls during a period of recession. Eventually it starts upward again (at time t₂). The point at which a recession ends and an expansion begins is called the troughThe point of the business cycle at which a recession ends and an expansion begins. of the business cycle. The expansion continues until another peak is reached at time t₃.Some economists prefer to break the expansion phase into two parts. The recovery phase is said to be the period between the previous trough and the time when the economy achieves its previous peak level of real GDP. The “expansion” phase is from that point until the following peak. A complete business cycle is defined by the passage from one peak to the next.

Because the Business Cycle Dating Committee dates peaks and troughs by specific months, and because real GDP is estimated only on a quarterly basis by the Bureau of Economic Analysis, the committee relies on a variety of other indicators that are published monthly, including real personal income, employment, industrial production, and real wholesale and retail sales. The committee typically determines that a recession has happened long after it has actually begun and sometimes ended! In large part, that avoids problems when data released about the economy are revised, and the committee avoids having to reverse itself on its determination of when a recession begins or ends, something it has never done. In December 2008, the committee announced that a recession in the United States had begun in December 2007. In September 2010, the committee announced that this recession had ended in June 2009.

Business Cycles and the Growth of Real GDP in the United States

Figure 5.2 "Expansions and Recessions, 1960–2011" shows movements in real GDP in the United States from 1960 to 2011. Over those years, the economy experienced eight recessions, shown by the shaded areas in the chart. Although periods of expansion have been more prolonged than periods of recession, we see the cycle of economic activity that characterizes economic life.

Figure 5.2 Expansions and Recessions, 1960–2011

The chart shows movements in real GDP since 1960. Recessions—periods of falling real GDP—are shown as shaded areas. On average, the annual rate of growth of real GDP over the period was 3.1% per year.

Source: Bureau of Economic Analysis, NIPA Table 1.1.6 (revised February 29, 2012). Real Gross Domestic Product, Chained Dollars [Billions of chained (2005) dollars]. Seasonally adjusted at annual rates.

Real GDP clearly grew between 1960 and 2011. While the economy experienced expansions and recessions, its general trend during the period was one of rising real GDP. The average annual rate of growth of real GDP was about 3.1%.

During the post–World War II period, the average expansion has lasted 58 months, and the average recession has lasted about 11 months. The 2001 recession, which lasted eight months, was thus slightly shorter than the average. The 2007–2009 recession lasted 18 months; it was the longest of the post–World War II period.

Economists have sought for centuries to explain the forces at work in a business cycle. Not only are the currents that move the economy up or down intellectually fascinating but also an understanding of them is of tremendous practical importance. A business cycle is not just a movement along a curve in a textbook. It is new jobs for people, or the loss of them. It is new income, or the loss of it. It is the funds to build new schools or to provide better health care—or the lack of funds to do all those things. The story of the business cycle is the story of progress and plenty, of failure and sacrifice.

During the most recent recession, the job outlook for college graduates deteriorated. According to a National Association of Colleges and Employers study, 20% of college graduates seeking jobs were able to obtain one after graduation in 2009. In 2010, that percentage rose to 24%, but the average salary had slipped 1.7% from the previous year. The unemployment rate for college graduates under age 25 rose from 3.7% in April 2007 to 8% in April 2010. Over the same two-year period, the unemployment rate for high school graduates who had never enrolled in college rose from 11.4% to 24.5%.Steven Greenhouse, “Job Market Gets Better for U.S. Graduates, but Only Slightly: Offers Will Increase 5% Over Last Year; Average Starting Salaries Are Down,” The International Herald Tribune, May 26, 2010, Finance 16.

The effects of recessions extend beyond the purely economic realm and influence the social fabric of society as well. Suicide rates and property crimes—burglary, larceny, and motor vehicle theft tend to rise during recessions. Even popular music appears to be affected. Terry F. Pettijohn II, a psychologist at Coastal Carolina University, has studied Billboard No. 1 songs from 1955 to 2003. He finds that during recessions, popular songs tend to be longer and slower, and to have more serious lyrics. “It’s ‘Bridge over Troubled Water’ or ‘That’s What Friends Are For’,” he says. During expansions, songs tend to be faster, shorter, and somewhat sillier, such as “At the Hop” or “My Sharona.”Tamar Lewin, “A Hemline Index, Updated,” New York Times, October 19, 2008, Section WK, 1.

In our study of macroeconomics, we will gain an understanding of the forces at work in the business cycle. We will also explore policies through which the public sector might act to make recessions less severe and, perhaps, to prolong expansions. We turn next to an examination of price-level changes and unemployment.

Case in Point: The Art of Predicting Recessions

People who make a living tracking the economy and trying to predict its future do not do a very good job at predicting turning points in economic activity. The 52 economists surveyed by the Wall Street Journal each month did predict that the economy would slip into a recession in the third quarter of 2008. They made that prediction, however, in October—after the third quarter had ended. In September, the last month of the third quarter, the average forecast among the 52 economists had the economy continuing to grow through the third and fourth quarters of 2008. That September survey was taken before the financial crisis hit, a crisis that took virtually everyone by surprise. Of course, as we have already noted, the third-quarter downturn had not been identified as a recession by the NBER’s Business Cycle Dating Committee as of November of 2008.

Predicting business cycle turning points has always been a tricky business. The experience of the recession of 2001 illustrates this. As the accompanying table shows, even as late as September 10, 2001, only 13 out of the 100 Blue Chip forecasters had answered in the affirmative to the question, “Has the United States slipped into a recession?” even though we now know the recession had begun the previous March. Comparing the data that were originally released by the U.S. Bureau of Economic Analysis shortly after the end of each quarter with the revised data that were released after July 2002 provides an important insight into explaining why the forecasters seem to have done so badly. As the graph on pre-revision and post-revision estimates of real GDP growth shows, the data released shortly after the end of each quarter showed an economy expanding through the second quarter of 2001, whereas the revised data show the economy contracting modestly in the first quarter of 2001 and then more forcefully in the second quarter. Only after the attacks on the World Trade Center in New York City and the Pentagon in Washington, D.C., on September 11, 2001, did most of the Blue Chip forecasters realize the economy was in recession.

The National Bureau of Economic Research (NBER) Business Cycle Dating Committee in November 2001 released a press announcement dating the onset of the recession as March 2001. The committee argued that “before the attacks of September 11, it is possible that the decline in the economy would have been too mild to qualify as a recession. The attacks clearly deepened the contraction and may have been an important factor in turning the episode into a recession.” While surprising at the time, the revised data suggest that the committee made a good call.

This episode in economic history also points out the difference between the common definition of a recession as two consecutive quarters of declining real GDP and the NBER Dating Committee’s continued insistence that it does not define a recession in this way. Rather the committee looks not only at real GDP but also at employment, income, and other factors. The behavior of employment during 2001 seems to have been an important factor in the November 2001 decision to proclaim March 2001 as the peak despite the misleading information on real GDP coming out of the Bureau of Economic Analysis at the time. The slow pickup in employment may also, though, have made it hesitate to call November 2001 the trough until July 2003.

Question posed: “Has the United States slipped into a recession?”
Date	Percent of Blue Chip responders answering “Yes”	Percent of Blue Chip responders answering “No”
February 2001	5	95
June 2001	7	93
July 2001	13	87
August 2001	5	85
September 10, 2001	13	87
September 19, 2001	82	18

Sources: Phil Izzo, “Economists Expect Crisis to Deepen,” Wall Street Journal Online, October 10, 2008; Kevin L. Kliesen, “The 2001 Recession: How Was It Different and What Developments May Have Caused It?” Federal Reserve Bank of St. Louis Review, September/October 2003: 23–37; http://www.nber.org/cycles/; “Press Release,” Business Cycle Dating Committee, National Bureau of Economic Research, press release, Cambridge, Massachusetts, July 17, 2002.

Answer to Try It! Problem

Why Do We Care?

What difference does it make if the average level of prices changes? First, consider the impact of inflation.

Inflation is measured as the annual rate of increase in the average level of prices. Figure 5.3 "Inflation, 1960–2011" shows how volatile inflation has been in the United States over the past four decades. In the 1960s the inflation rate rose, and it became dramatically worse in the 1970s. The inflation rate plunged in the 1980s and continued to ease downward in the 1990s. It remained low in the early 2000s, began to accelerate in 2007, and has remained low since then.

Figure 5.3 Inflation, 1960–2011

The U.S. inflation rate, measured as the annual rate of change in the average level of prices paid by consumers, varied considerably over the 1960–2011 period.

Source: Bureau of Labor Statistics, All Urban Consumers CPI-U, 1982–84 = 100, Dec.–Dec. inflation rate.

Whether one regards inflation as a “good” thing or a “bad” thing depends very much on one’s economic situation. If you are a borrower, unexpected inflation is a good thing—it reduces the value of money that you must repay. If you are a lender, it is a bad thing because it reduces the value of future payments you will receive. Whatever any particular person’s situation may be, inflation always produces the following effects on the economy: it reduces the value of money and it reduces the value of future monetary obligations. It can also create uncertainty about the future.

Suppose that you have just found a $10 bill you stashed away in 1990. Prices have increased by about 50% since then; your money will buy less than what it would have purchased when you put it away. Your money has thus lost value.

Money loses value when its purchasing power falls. Since inflation is a rise in the level of prices, the amount of goods and services a given amount of money can buy falls with inflation.

Just as inflation reduces the value of money, it reduces the value of future claims on money. Suppose you have borrowed $100 from a friend and have agreed to pay it back in one year. During the year, however, prices double. That means that when you pay the money back, it will buy only half as much as it could have bought when you borrowed it. That is good for you but tough on the person who lent you the money. Of course, if you and your friend had anticipated such rapid inflation, you might have agreed to pay back a larger sum to adjust for it. When people anticipate inflation, they can adjust for its consequences in determining future obligations. But unanticipated inflation helps borrowers and hurts lenders.

Inflation’s impact on future claims can be particularly hard on people who must live on a fixed income, that is, on an income that is predetermined through some contractual arrangement and does not change with economic conditions. An annuity, for example, typically provides a fixed stream of money payments. Retirement pensions sometimes generate fixed income. Inflation erodes the value of such payments.

Given the danger posed by inflation for people on fixed incomes, many retirement plans provide for indexed payments. An indexed payment is one whose dollar amount changes with the rate of change in the price level. If a payment changes at the same rate as the rate of change in the price level, the purchasing power of the payment remains constant. Social Security payments, for example, are indexed to maintain their purchasing power.

Because inflation reduces the purchasing power of money, the threat of future inflation can make people reluctant to lend for long periods. From a lender’s point of view, the danger of a long-term commitment of funds is that future inflation will wipe out the value of the amount that will eventually be paid back. Lenders are reluctant to make such commitments.

Uncertainty can be particularly pronounced in countries where extremely high inflation is a threat. HyperinflationAn inflation rate in excess of 200% per year. is generally defined as an inflation rate in excess of 200% per year. It is always caused by the rapid printing of money. Several countries have endured episodes of hyperinflation. The worst case was in Hungary immediately after World War II, when Hungary’s price level was tripling every day. The second-worst case of hyperinflation belongs to Zimbabwe, which is the first country to have experienced hyperinflation in the 21st century. Zimbabwe’s price index was doubling daily: a loaf of bread that cost 200,000 Zimbabwe dollars in February 2008 cost 1.6 trillion Zimbabwe dollars by August.“Zimbabwe Inflation Hits 11,200,000%,” CNN.com, August 19, 2008, available at http://edition.cnn.com/2008/BUSINESS/08/19/zimbabwe.inflation/index.html. The annual inflation rate reached 89.7 sextillion percent in November of that year.Steve H. Hanke, “R.I.P. Zimbabwe Dollar,” Cato Institute, May 3, 2010, available at http://www.cato.org/zimbabwe. (On the off chance you haven’t been counting in the sextillions a lot lately, 89.7 sextillion equates to 897 followed by 20 zeroes.) Two months later, Zimbabwe finally gave up on printing money and took the Zimbabwe dollar out of circulation. Exchange is now carried out using U.S. dollars or South African rand—and Zimbabwe’s period of hyperinflation has come to an end.

Do the problems associated with inflation imply that deflation would be a good thing? The answer is simple: no. Like inflation, deflation changes the value of money and the value of future obligations. It also creates uncertainty about the future.

If there is deflation, the real value of a given amount of money rises. In other words, if there had been deflation since 2000, a $10 bill you had stashed away in 2000 would buy more goods and services today. That sounds good, but should you buy $10 worth of goods and services now when you would be able to buy even more for your $10 in the future if the deflation continues? When Japan experienced deflation in the late 1990s and early 2000s, Japanese consumers seemed to be doing just that—waiting to see if prices would fall further. They were spending less per person and, as we will see throughout our study of macroeconomics, less consumption often meant less output, fewer jobs, and the prospect of a recurring recession.

And, if you had to use the $10 to pay back a debt you owed, the purchasing power of your money would be higher than when you borrowed the money. The lender would feel good about being able to buy more with the $10 than you were able to, but you would feel like you had gotten a raw deal.

Unanticipated deflation hurts borrowers and helps lenders. If the parties anticipate the deflation, a loan agreement can be written to reflect expected changes in the price level.

The threat of deflation can make people reluctant to borrow for long periods. Borrowers become reluctant to enter into long-term contracts because they fear that deflation will raise the value of the money they must pay back in the future. In such an environment, firms may be reluctant to borrow to build new factories, for example. This is because they fear that the prices at which they can sell their output will drop, making it difficult for them to repay their loans.

Deflation was common in the United States in the latter third of the 19th century. In the 20th century, there was a period of deflation after World War I and again during the Great Depression in the 1930s.

Price Indexes

How do we actually measure inflation and deflation (that is, changes in the price level)? Price-level change is measured as the percentage rate of change in the level of prices. But how do we find a price level?

Economists measure the price level with a price index. A price indexA number whose movement reflects movement in the average level of prices. is a number whose movement reflects movement in the average level of prices. If a price index rises 10%, it means the average level of prices has risen 10%.

There are four steps one must take in computing a price index:

1. Select the kinds and quantities of goods and services to be included in the index. A list of these goods and services, and the quantities of each, is the “market basket” for the index.
2. Determine what it would cost to buy the goods and services in the market basket in some period that is the base period for the index. A base periodA time period against which costs of the market basket in other periods will be compared in computing a price index. is a time period against which costs of the market basket in other periods will be compared in computing a price index. Most often, the base period for an index is a single year. If, for example, a price index had a base period of 1990, costs of the basket in other periods would be compared to the cost of the basket in 1990. We will encounter one index, however, whose base period stretches over three years.
3. Compute the cost of the market basket in the current period.
4. Compute the price index. It equals the current cost divided by the base-period cost of the market basket.

(While published price indexes are typically reported with this number multiplied by 100, our work with indexes will be simplified by omitting this step.)

Suppose that we want to compute a price index for movie fans, and a survey of movie watchers tells us that a typical fan rents 4 movies on DVD and sees 3 movies in theaters each month. At the theater, this viewer consumes a medium-sized soft drink and a medium-sized box of popcorn. Our market basket thus might include 4 DVD rentals, 3 movie admissions, 3 medium soft drinks, and 3 medium servings of popcorn.

Our next step in computing the movie price index is to determine the cost of the market basket. Suppose we surveyed movie theaters and DVD-rental stores in 2011 to determine the average prices of these items, finding the values given in Table 5.1 "Pricing a Market Basket". At those prices, the total monthly cost of our movie market basket in 2011 was $48. Now suppose that in 2012 the prices of movie admissions and DVD rentals rise, soft-drink prices at movies fall, and popcorn prices remain unchanged. The combined effect of these changes pushes the 2012 cost of the basket to $50.88.

Using the data in Table 5.1 "Pricing a Market Basket", we could compute price indexes for each year. Recall that a price index is the ratio of the current cost of the basket to the base-period cost. We can select any year we wish as the base year; take 2011. The 2012 movie price index (MPI) is thus

The value of any price index in the base period is always 1. In the case of our movie price index, the 2011 index would be the current (2011) cost of the basket, $48, divided by the base-period cost, which is the same thing: $48/$48 = 1.

Computing the Rate of Inflation or Deflation

The rate of inflation or deflation is the percentage rate of change in a price index between two periods. Given price-index values for two periods, we can calculate the rate of inflation or deflation as the change in the index divided by the initial value of the index, stated as a percentage:

To calculate inflation in movie prices over the 2011–2012 period, for example, we could apply Equation 5.4 to the price indexes we computed for those two years as follows:

The CPI is often used for calculating price-level change for the economy. For example, the rate of inflation in 2011 can be computed from the December 2010 price level (2.186) and the December 2011 level (2.263):

Computing Real Values Using Price Indexes

Suppose your uncle started college in 2001 and had a job busing dishes that paid $5 per hour. In 2011 you had the same job; it paid $6 per hour. Which job paid more?

At first glance, the answer is straightforward: $6 is a higher wage than $5. But $1 had greater purchasing power in 2001 than in 2011 because prices were lower in 2001 than in 2011. To obtain a valid comparison of the two wages, we must use dollars of equivalent purchasing power. A value expressed in units of constant purchasing power is a real valueA value expressed in units of constant purchasing power.. A value expressed in dollars of the current period is called a nominal valueA value expressed in dollars of the current period.. The $5 wage in 2001 and the $6 wage in 2011 are nominal wages.

To convert nominal values to real values, we divide by a price index. The real value for a given period is the nominal value for that period divided by the price index for that period. This procedure gives us a value in dollars that have the purchasing power of the base period for the price index used. Using the CPI, for example, yields values expressed in dollars of 1982–1984 purchasing power, the base period for the CPI. The real value of a nominal amount X at time t, X_t, is found using the price index for time t:

Let us compute the real value of the $6 wage for busing dishes in 2011 versus the $5 wage paid to your uncle in 2001. The CPI in 2001 was 177.1; in 2011 it was 224.9. Real wages for the two years were thus

Given the nominal wages in our example, you earned about 5% less in real terms in 2011 than your uncle did in 2001.

Price indexes are useful. They allow us to see how the general level of prices has changed. They allow us to estimate the rate of change in prices, which we report as the rate of inflation or deflation. And they give us a tool for converting nominal values to real values so we can make better comparisons of economic performance across time.

Are Price Indexes Accurate Measures of Price-Level Changes?

Price indexes that employ fixed market baskets are likely to overstate inflation (and understate deflation) for four reasons:

1. Because the components of the market basket are fixed, the index does not incorporate consumer responses to changing relative prices.
2. A fixed basket excludes new goods and services.
3. Quality changes may not be completely accounted for in computing price-level changes.
4. The type of store in which consumers choose to shop can affect the prices they pay, and the price indexes do not reflect changes consumers have made in where they shop.

To see how these factors can lead to inaccurate measures of price-level changes, suppose the price of chicken rises and the price of beef falls. The law of demand tells us that people will respond by consuming less chicken and more beef. But if we use a fixed market basket of goods and services in computing a price index, we will not be able to make these adjustments. The market basket holds constant the quantities of chicken and beef consumed. The importance in consumer budgets of the higher chicken price is thus overstated, while the importance of the lower beef price is understated. More generally, a fixed market basket will overstate the importance of items that rise in price and understate the importance of items that fall in price. This source of bias is referred to as the substitution bias.

The new-product bias, a second source of bias in price indexes, occurs because it takes time for new products to be incorporated into the market basket that makes up the CPI. A good introduced to the market after the basket has been defined will not, of course, be included in it. But a new good, once successfully introduced, is likely to fall in price. When VCRs were first introduced, for example, they generally cost more than $1,000. Within a few years, an equivalent machine cost less than $200. But when VCRs were introduced, the CPI was based on a market basket that had been defined in the early 1970s. There was no VCR in the basket, so the impact of this falling price was not reflected in the index. The DVD player was introduced into the CPI within a year of its availability.

A third price index bias, the quality-change bias, comes from improvements in the quality of goods and services. Suppose, for example, that Ford introduces a new car with better safety features and a smoother ride than its previous model. Suppose the old model cost $20,000 and the new model costs $24,000, a 20% increase in price. Should economists at the Bureau of Labor Statistics (BLS) simply record the new model as being 20% more expensive than the old one? Clearly, the new model is not the same product as the old model. BLS economists faced with such changes try to adjust for quality. To the extent that such adjustments understate quality change, they overstate any increase in the price level.

The fourth source of bias is called the outlet bias. Households can reduce some of the impact of rising prices by shopping at superstores or outlet stores (such as T.J. Maxx, Wal-Mart, or factory outlet stores), though this often means they get less customer service than at traditional department stores or at smaller retail stores. However, since such shopping has increased in recent years, it must be that for their customers, the reduction in prices has been more valuable to them than loss of service. Prior to 1998, the CPI did not account for a change in the number of households shopping at these newer kinds of stores in a timely manner, but the BLS now does quarterly surveys and updates its sample of stores much more frequently. Another form of this bias arises because the government data collectors do not collect price data on weekends and holidays, when many stores run sales.

Economists differ on the degree to which these biases result in inaccuracies in recording price-level changes. In late 1996, Michael Boskin, an economist at Stanford University, chaired a panel of economists appointed by the Senate Finance Committee to determine the magnitude of the problem in the United States. The panel reported that the CPI was overstating inflation in the United States by 0.8 to 1.6 percentage points per year. Their best estimate was 1.1 percentage points, as shown in Table 5.2 "Estimates of Bias in the Consumer Price Index". Since then, the Bureau of Labor Statistics has made a number of changes to correct for these sources of bias and since August 2002 has reported a new consumer price index called the Chained Consumer Price Index for all Urban Consumers (C-CPU-U) that attempts to provide a closer approximation to a “cost-of-living” index by utilizing expenditure data that reflect the substitutions that consumers make across item categories in response to changes in relative prices.Robert Cage, John Greenlees, and Patrick Jackman, “Introducing the Chained Consumer Price Index” (paper, Seventh Meeting of the International Working Group on Price Indices, Paris, France, May 2003), available at http://stats.bls.gov/cpi/superlink.htm. However, a 2006 study by Robert Gordon, a professor at Northwestern University and a member of the original 1996 Boskin Commission, estimates that the total bias is still about 0.8 percentage points per year, as also shown in Table 5.2 "Estimates of Bias in the Consumer Price Index".

Table 5.2 Estimates of Bias in the Consumer Price Index

Sources of Bias	1997 Estimate	2006 Estimate
Substitution	0.4	0.4
New products and quality change	0.6	0.3
Switching to new outlets	0.1	0.1
Total	1.1	0.8
Plausible range	0.8–1.6	—

The Boskin Commission reported that the CPI overstates the rate of inflation by 0.8 to 1.6 percentage points due to the biases shown, with a best-guess estimate of 1.1. A 2006 study by Robert Gordon estimates that the bias fell but is still about 0.8 percentage points.

Source: Robert J. Gordon, “The Boskin Commission Report: A Retrospective One Decade Later” (National Bureau of Economic Research Working Paper 12311, June 2006), available at http://www.nber.org/papers/w12311.

These findings of upward bias have enormous practical significance. With annual inflation running below 2% in three out of the last 10 years and averaging 2.7% over the 10 years, it means that the United States has come close to achieving price stability for almost a decade.

To the extent that the computation of price indexes overstates the rate of inflation, then the use of price indexes to correct nominal values results in an understatement of gains in real incomes. For example, average nominal hourly earnings of U.S. production workers were $13.01 in 1998 and $17.42 in 2007. Adjusting for CPI-measured inflation, the average real hourly earnings was $7.98 in 1998 and $8.40 in 2007, suggesting that real wages rose about 5.3% over the period. If inflation was overstated by 0.8% per year over that entire period, as suggested by Gordon’s updating of the Boskin Commission’s best estimate, then, adjusting for this overstatement, real wages should have been reported as $7.98 for 1998 and $9.01 for 2007, a gain of nearly 13%.

Also, because the CPI is used as the basis for calculating U.S. government payments for programs such as Social Security and for adjusting tax brackets, this price index affects the government’s budget balance, the difference between government revenues and government expenditures. The Congressional Budget Office has estimated that correcting the biases in the index would have increased revenue by $2 billion and reduced outlays by $4 billion in 1997. By 2007, the U.S. government’s budget would have had an additional $140 billion if the bias were removed.

Key Takeaways

• Inflation is an increase in the average level of prices, and deflation is a decrease in the average level of prices. The rate of inflation or deflation is the percentage rate of change in a price index.
• The consumer price index (CPI) is the most widely used price index in the United States.
• Nominal values can be converted to real values by dividing by a price index.
• Inflation and deflation affect the real value of money, of future obligations measured in money, and of fixed incomes. Unanticipated inflation and deflation create uncertainty about the future.
• Economists generally agree that the CPI and other price indexes that employ fixed market baskets of goods and services do not accurately measure price-level changes. Biases include the substitution bias, the new-product bias, the quality-change bias, and the outlet bias.

Try It!

Suppose that nominal GDP is $10 trillion in 2003 and $11 trillion in 2004, and that the implicit price deflator has gone from 1.063 in 2003 to 1.091 in 2004. Compute real GDP in 2003 and 2004. Using the percentage change in the implicit price deflator as the gauge, what was the inflation rate over the period?

Case in Point: Take Me Out to the Ball Game …

The cost of a trip to the old ball game rose 2% in 2011, according to Team Marketing Report, a Chicago-based newsletter. The report bases its estimate on its fan price index, whose market basket includes four adult average-priced tickets, two small draft beers, four small soft drinks, four regular-sized hot dogs, parking for one car, two game programs, and two least expensive, adult-sized adjustable baseball caps. The average price of the market basket was $197.35 in 2011.

Team Marketing compiles the cost of the basket for each of major league baseball’s 30 teams. According to this compilation, the Boston Red Sox was the most expensive team to watch in 2011; the Arizona Diamondbacks was the cheapest. The table shows the cost of the fan price index market basket for 2011.

Source: Team Marketing Report, “TMR’s Fan Cost Index Major League Baseball 2011,” available at http://www.teammarketing.com.

Team	Basket Cost	Team	Basket Cost
Boston Red Sox	$339.01	Baltimore Orioles	$174.10
New York Yankees	$338.32	Cleveland Indians	$170.96
Chicago Cubs	$305.60	Florida Marlins	$170.24
Chicago White Sox	$258.68	Atlanta Braves	$169.02
New York Mets	$241.74	Cincinnati Reds	$162.24
Philadelphia Phillies	$240.66	Colorado Rockies	$161.00
Los Angeles Dodgers	$226.36	Milwaukee Brewers	$160.40
St. Louis Cardinals	$223.18	Kansas City Royals	$159.80
Houston Astros	$221.36	Texas Rangers	$159.40
Minnesota Twins	$213.16	Tampa Bay Rays	$139.68
Toronto Blue Jays	$212.68	Los Angeles Angels	$129.50
San Francisco Giants	$208.15	Pittsburgh Pirates	$127.71
Detroit Tigers	$207.28	San Diego Padres	$125.81
Washington Nationals	$196.34	Arizona Diamondbacks	$120.96
Seattle Mariners	$183.59
Oakland Athletics	$178.09	MLB Average	$197.35

Answer to Try It! Problem

Rearranging Equation 5.3, real GDP = nominal GDP/implicit price deflator. Therefore,

Real GDP in 2003 = $10 trillion/1.063 = $9.4 trillion. Real GDP in 2004 = $11 trillion/1.091 = $10.1 trillion.

Thus, in this economy in real terms, GDP has grown by $0.7 trillion.

To find the rate of inflation, we refer to Equation 5.4, and we calculate:

Inflation rate in 2004 = (1.091 − 1.063)/1.063 = 0.026 = 2.6%

Thus, the price level rose 2.6% between 2003 and 2004.

Measuring Unemployment

The Bureau of Labor Statistics defines a person as unemployed if he or she is not working but is looking for and available for work. The labor forceThe total number of people working or unemployed. is the total number of people working or unemployed. The unemployment rateThe percentage of the labor force that is unemployed. is the percentage of the labor force that is unemployed.

To estimate the unemployment rate, government surveyors fan out across the country each month to visit roughly 60,000 households. At each of these randomly selected households, the surveyor asks about the employment status of each adult (everyone age 16 or over) who lives there. Many households include more than one adult; the survey gathers information on about roughly 100,000 adults. The surveyor asks if each adult is working. If the answer is yes, the person is counted as employed. If the answer is no, the surveyor asks if that person has looked for work at some time during the previous four weeks and is available for work at the time of the survey. If the answer to that question is yes, the person is counted as unemployed. If the answer is no, that person is not counted as a member of the labor force. Figure 5.4 "Computing the Unemployment Rate" shows the survey’s results for the civilian (nonmilitary) population for February 2012. The unemployment rate is then computed as the number of people unemployed divided by the labor force—the sum of the number of people not working but available and looking for work plus the number of people working. In February 2012, the unemployment rate was 8.3%.

Figure 5.4 Computing the Unemployment Rate

A monthly survey of households divides the civilian adult population into three groups. Those who have jobs are counted as employed; those who do not have jobs but are looking for them and are available for work are counted as unemployed; and those who are not working and are not looking for work are not counted as members of the labor force. The unemployment rate equals the number of people looking for work divided by the sum of the number of people looking for work and the number of people employed. Values are for February 2012. All numbers are in thousands.

There are several difficulties with the survey. The old survey, designed during the 1930s, put the “Are you working?” question differently depending on whether the respondent was a man or woman. A man was asked, “Last week, did you do any work for pay or profit?” A woman was asked, “What were you doing for work last week, keeping house or something else?” Consequently, many women who were looking for paid work stated that they were “keeping house”; those women were not counted as unemployed. The BLS did not get around to fixing the survey—asking women the same question it asked men—until 1994. The first time the new survey question was used, the unemployment rate among women rose by 0.5 percentage point. More than 50 million women are in the labor force; the change added more than a quarter of a million workers to the official count of the unemployed.For a description of the new survey and other changes introduced in the method of counting unemployment, see Janet L. Norwood and Judith M. Tanur, “Unemployment Measures for the Nineties,” Public Opinion Quarterly 58, no. 2 (Summer 1994): 277–94.

The problem of understating unemployment among women has been fixed, but others remain. A worker who has been cut back to part-time work still counts as employed, even if that worker would prefer to work full time. A person who is out of work, would like to work, has looked for work in the past year, and is available for work, but who has given up looking, is considered a discouraged worker. Discouraged workers are not counted as unemployed, but a tally is kept each month of the number of discouraged workers.

The official measures of employment and unemployment can yield unexpected results. For example, when firms expand output, they may be reluctant to hire additional workers until they can be sure the demand for increased output will be sustained. They may respond first by extending the hours of employees previously reduced to part-time work or by asking full-time personnel to work overtime. None of that will increase employment, because people are simply counted as “employed” if they are working, regardless of how much or how little they are working. In addition, an economic expansion may make discouraged workers more optimistic about job prospects, and they may resume their job searches. Engaging in a search makes them unemployed again—and increases unemployment. Thus, an economic expansion may have little effect initially on employment and may even increase unemployment.

Types of Unemployment

Workers may find themselves unemployed for different reasons. Each source of unemployment has quite different implications, not only for the workers it affects but also for public policy.

Figure 5.5 "The Natural Level of Employment" applies the demand and supply model to the labor market. The price of labor is taken as the real wage, which is the nominal wage divided by the price level; the symbol used to represent the real wage is the Greek letter omega, ω. The supply curve is drawn as upward sloping, though steep, to reflect studies showing that the quantity of labor supplied at any one time is nearly fixed. Thus, an increase in the real wage induces a relatively small increase in the quantity of labor supplied. The demand curve shows the quantity of labor demanded at each real wage. The lower the real wage, the greater the quantity of labor firms will demand. In the case shown here, the real wage, ω_e, equals the equilibrium solution defined by the intersection of the demand curve D₁ and the supply curve S₁. The quantity of labor demanded, L_e, equals the quantity supplied. The employment level at which the quantity of labor demanded equals the quantity supplied is called the natural level of employmentThe employment level at which the quantity of labor demanded equals the quantity supplied.. It is sometimes referred to as full employment.

Figure 5.5 The Natural Level of Employment

The employment level at which the quantity of labor demanded equals the quantity supplied is called the natural level of employment. Here, the natural level of employment is L_e, which is achieved at a real wage ω_e.

Even if the economy is operating at its natural level of employment, there will still be some unemployment. The rate of unemployment consistent with the natural level of employment is called the natural rate of unemploymentThe rate of unemployment consistent with the natural level of employment.. Business cycles may generate additional unemployment. We discuss these various sources of unemployment below.

Cyclical Unemployment

Of course, the economy may not be operating at its natural level of employment, so unemployment may be above or below its natural level. In a later chapter we will explore what happens when the economy generates employment greater or less than the natural level. Cyclical unemploymentUnemployment in excess of the unemployment that exists at the natural level of employment. is unemployment in excess of the unemployment that exists at the natural level of employment.

Figure 5.6 "Unemployment Rate, 1960–2011" shows the unemployment rate in the United States for the period from 1960 through 2011. We see that it has fluctuated considerably. How much of it corresponds to the natural rate of unemployment varies over time with changing circumstances. For example, in a country with a demographic “bulge” of new entrants into the labor force, frictional unemployment is likely to be high, because it takes the new entrants some time to find their first jobs. This factor alone would raise the natural rate of unemployment. A demographic shift toward more mature workers would lower the natural rate. During recessions, highlighted in Figure 5.6 "Unemployment Rate, 1960–2011", the part of unemployment that is cyclical unemployment grows. The analysis of fluctuations in the unemployment rate, and the government’s responses to them, will occupy center stage in much of the remainder of this book.

Figure 5.6 Unemployment Rate, 1960–2011

The chart shows the unemployment rate for each year from 1960 to 2011. Recessions are shown as shaded areas.

Source: Economic Report of the President, 2012, Table B-42.

Key Takeaways

• People who are not working but are looking and available for work at any one time are considered unemployed. The unemployment rate is the percentage of the labor force that is unemployed.
• When the labor market is in equilibrium, employment is at the natural level and the unemployment rate equals the natural rate of unemployment.
• Even if employment is at the natural level, the economy will experience frictional and structural unemployment. Cyclical unemployment is unemployment in excess of that associated with the natural level of employment.

Try It!

Given the data in the table, compute the unemployment rate in Year 1 and in Year 2. Explain why, in this example, both the number of people employed and the unemployment rate increased.

Year	Number employed (in millions)	Number unemployed (in millions)
1	20	2
2	21	2.4

Case in Point: Might Increased Structural Unemployment Explain the “Jobless Recovery” Following the 2001 Recession?

The U.S. 2001 recession was mild by historical standards, but recovery in terms of increased employment seemed painfully slow in coming. Economists Erica Goshen and Simon Potter at the Federal Reserve Bank of New York think the reason for the slow recovery in jobs may have actually reflected structural changes in the U.S. economy. They argue that during the recession permanent rather than temporary layoffs predominated and that it takes longer for firms to hire workers into new positions than to hire them back into former jobs.

What is their evidence? When the layoff is temporary, the employer “suspends” the job, due to slack demand, and the employee expects to be recalled once demand picks up. With a permanent layoff, the employer eliminates the job. So, they looked at the contribution of temporary layoffs to the unemployment rate during the recent recession compared to the situation in the four recessions before 1990. In the earlier recessions, unemployment from temporary layoffs rose when the economy was shrinking and fell after the economy began to recover. In both the 1991 and 2001 recessions, temporary layoffs were minor. Then, the authors examined job flows in 70 industries. They classified layoffs in an industry as being cyclical in nature if the job losses during the recession were reversed during the recovery but structural if job losses for the industry continued during the recovery. Their analysis revealed that during the recession of the early 1980s, job losses were about evenly split between cyclical and structural changes. In the 1991 recession and then more strongly in the 2001 recession, structural changes dominated. “Most of the industries that lost jobs during the [2001] recession—for example, communications, electronic equipment, and securities and commodities brokers—[were] still losing jobs” in 2003. “The trend revealed . . . is one in which jobs are relocated from some industries to others, not reclaimed by the same industries that lost them earlier.”

The authors suggest three possible reasons for the recent increased role of structural change: (1) The structural decline in some industries could be the result of overexpansion in those industries during the 1990s. The high tech and telecommunications industries in particular could be examples of industries that were overbuilt before the 2001 recession. (2) Improved government policies may have reduced cyclical unemployment. Examination of macroeconomic policy in future chapters will return to this issue. (3) New management strategies to reduce costs may be promoting leaner staffing. For firms adopting such strategies, a recession may provide an opportunity to reorganize the production process permanently and reduce payrolls in the process.

Goshen and Potter point out that, for workers, finding new jobs is harder than simply returning to old ones. For firms, making decisions about the nature of new jobs is time consuming at best. The uncertainty created by the war in Iraq and the imposition of new accounting standards following the “Enron”-like scandals may have further prolonged the creation of new jobs.

Source: Erica L. Goshen and Simon Potter, “Has Structural Change Contributed to a Jobless Recovery?” Federal Reserve Bank of New York Current Issues in Economics and Finance 9, no. 8 (August 2003): 1–7.

Answer to Try It! Problem

In Year 1 the total labor force includes 22 million workers, and so the unemployment rate is 2/22 = 9.1%. In Year 2 the total labor force numbers 23.4 million workers; therefore the unemployment rate is 2.4/23.4 = 10.3%. In this example, both the number of people employed and the unemployment rate rose, because more people (23.4 − 22 = 1.4 million) entered the labor force, of whom 1 million found jobs and 0.4 million were still looking for jobs.

The Components of GDP

We can divide the goods and services produced during any period into four broad components, based on who buys them. These components of GDP are personal consumption (C), gross private domestic investment (I), government purchases (G), and net exports (X_n). Thus

We will examine each of these components, and we will see how each fits into the pattern of macroeconomic activity. Before we begin, it will be helpful to distinguish between two types of variables: stocks and flows. A flow variableA variable that is measured over a specific period of time. is a variable that is measured over a specific period of time. A stock variableA variable that is independent of time. is a variable that is independent of time. Income is an example of a flow variable. To say one’s income is, for example, $1,000 is meaningless without a time dimension. Is it $1,000 per hour? Per day? Per week? Per month? Until we know the time period, we have no idea what the income figure means. The balance in a checking account is an example of a stock variable. When we learn that the balance in a checking account is $1,000, we know precisely what that means; we do not need a time dimension. We will see that stock and flow variables play very different roles in macroeconomic analysis.

Personal Consumption

Personal consumptionA flow variable that measures the value of goods and services purchased by households during a time period. is a flow variable that measures the value of goods and services purchased by households during a time period. Purchases by households of groceries, health-care services, clothing, and automobiles—all are counted as consumption.

The production of consumer goods and services accounts for about 70% of total output. Because consumption is such a large part of GDP, economists seeking to understand the determinants of GDP must pay special attention to the determinants of consumption. In a later chapter we will explore these determinants and the impact of consumption on economic activity.

Personal consumption represents a demand for goods and services placed on firms by households. In the chapter on demand and supply, we saw how this demand could be presented in a circular flow model of the economy. Figure 6.1 "Personal Consumption in the Circular Flow" presents a circular flow model for an economy that produces only personal consumption goods and services. (We will add the other components of GDP to the circular flow as we discuss them.) Spending for these goods flows from households to firms; it is the arrow labeled “Personal consumption.” Firms produce these goods and services using factors of production: labor, capital, and natural resources. These factors are ultimately owned by households. The production of goods and services thus generates income to households; we see this income as the flow from firms to households labeled “Factor incomes” in the exhibit.

Figure 6.1 Personal Consumption in the Circular Flow

Personal consumption spending flows from households to firms. In return, consumer goods and services flow from firms to households. To produce the goods and services households demand, firms employ factors of production owned by households. There is thus a flow of factor services from households to firms, and a flow of payments of factor incomes from firms to households.

In exchange for payments that flow from households to firms, there is a flow of consumer goods and services from firms to households. This flow is shown in Figure 6.1 "Personal Consumption in the Circular Flow" as an arrow going from firms to households. When you buy a soda, for example, your payment to the store is part of the flow of personal consumption; the soda is part of the flow of consumer goods and services that goes from the store to a household—yours.

Similarly, the lower arrow in Figure 6.1 "Personal Consumption in the Circular Flow" shows the flow of factors of production—labor, capital, and natural resources—from households to firms. If you work for a firm, your labor is part of this flow. The wages you receive are part of the factor incomes that flow from firms to households.

There is a key difference in our interpretation of the circular flow picture in Figure 6.1 "Personal Consumption in the Circular Flow" from our analysis of the same model in the demand and supply chapter. There, our focus was microeconomics, which examines individual units of the economy. In thinking about the flow of consumption spending from households to firms, we emphasized demand and supply in particular markets—markets for such things as blue jeans, haircuts, and apartments. In thinking about the flow of income payments from firms to households, we focused on the demand and supply for particular factors of production, such as textile workers, barbers, and apartment buildings. Because our focus now is macroeconomics, the study of aggregates of economic activity, we will think in terms of the total of personal consumption and the total of payments to households.

Private Investment

Gross private domestic investmentThe value of all goods produced during a period for use in the production of other goods and services. is the value of all goods produced during a period for use in the production of other goods and services. Like personal consumption, gross private domestic investment is a flow variable. It is often simply referred to as “private investment.” A hammer produced for a carpenter is private investment. A printing press produced for a magazine publisher is private investment, as is a conveyor-belt system produced for a manufacturing firm. Capital includes all the goods that have been produced for use in producing other goods; it is a stock variable. Private investment is a flow variable that adds to the stock of capital during a period.

Heads Up!

The term “investment” can generate confusion. In everyday conversation, we use the term “investment” to refer to uses of money to earn income. We say we have invested in a stock or invested in a bond. Economists, however, restrict “investment” to activities that increase the economy’s stock of capital. The purchase of a share of stock does not add to the capital stock; it is not investment in the economic meaning of the word. We refer to the exchange of financial assets, such as stocks or bonds, as financial investment to distinguish it from the creation of capital that occurs as the result of investment. Only when new capital is produced does investment occur. Confusing the economic concept of private investment with the concept of financial investment can cause misunderstanding of the way in which key components of the economy relate to one another.

Gross private domestic investment includes three flows that add to or maintain the nation’s capital stock: expenditures by business firms on new buildings, plants, tools, equipment, and software that will be used in the production of goods and services; expenditures on new residential housing; and changes in business inventories. Any addition to a firm’s inventories represents an addition to investment; a reduction subtracts from investment. For example, if a clothing store stocks 1,000 pairs of jeans, the jeans represent an addition to inventory and are part of gross private domestic investment. As the jeans are sold, they are subtracted from inventory and thus subtracted from investment.

By recording additions to inventories as investment and reductions from inventories as subtractions from investment, the accounting for GDP records production in the period in which it occurs. Suppose, for example, that Levi Strauss manufactures 1 million pairs of jeans late in 2011 and distributes them to stores at the end of December. The jeans will be added to inventory; they thus count as investment in 2011 and enter GDP for that year. Suppose they are sold in January 2012. They will be counted as consumption in GDP for 2012 but subtracted from inventory, and from investment. Thus, the production of the jeans will add to GDP in 2011, when they were produced. They will not count in 2012, save for any increase in the value of the jeans resulting from the services provided by the retail stores that sold them.

Private investment accounts for about 15% of GDP—but, at times, even less. Despite its relatively small share of total economic activity, private investment plays a crucial role in the macroeconomy for two reasons:

1. Private investment represents a choice to forgo current consumption in order to add to the capital stock of the economy. Private investment therefore adds to the economy’s capacity to produce and shifts its production possibilities curve outward. Investment is thus one determinant of economic growth, which is explored in another chapter.
2. Private investment is a relatively volatile component of GDP; it can change dramatically from one year to the next. Fluctuations in GDP are often driven by fluctuations in private investment. We will examine the determinants of private investment in a chapter devoted to the study of investment.

Private investment represents a demand placed on firms for the production of capital goods. While it is a demand placed on firms, it flows from firms. In the circular flow model in Figure 6.2 "Private Investment in the Circular Flow", we see a flow of investment going from firms to firms. The production of goods and services for consumption generates factor incomes to households; the production of capital goods for investment generates income to households as well.

Figure 6.2 Private Investment in the Circular Flow

Private investment constitutes a demand placed on firms by other firms. It also generates factor incomes for households. To simplify the diagram, only the spending flows are shown—the corresponding flows of goods and services have been omitted.

Figure 6.2 "Private Investment in the Circular Flow" shows only spending flows and omits the physical flows represented by the arrows in Figure 6.1 "Personal Consumption in the Circular Flow". This simplification will make our analysis of the circular flow model easier. It will also focus our attention on spending flows, which are the flows we will be studying.

Government Purchases

Government agencies at all levels purchase goods and services from firms. They purchase office equipment, vehicles, buildings, janitorial services, and so on. Many government agencies also produce goods and services. Police departments produce police protection. Public schools produce education. The National Aeronautics and Space Administration (NASA) produces space exploration.

Government purchasesThe sum of purchases of goods and services from firms by government agencies plus the total value of output produced by government agencies themselves during a time period. are the sum of purchases of goods and services from firms by government agencies plus the total value of output produced by government agencies themselves during a time period. Government purchases make up about 20% of GDP.

Government purchases are not the same thing as government spending. Much government spending takes the form of transfer paymentsPayments that do not require the recipient to produce a good or service in order to receive them., which are payments that do not require the recipient to produce a good or service in order to receive them. Transfer payments include Social Security and other types of assistance to retired people, welfare payments to poor people, and unemployment compensation to people who have lost their jobs. Transfer payments are certainly significant—they account for roughly half of all federal government spending in the United States. They do not count in a nation’s GDP, because they do not reflect the production of a good or service.

Government purchases represent a demand placed on firms, represented by the flow shown in Figure 6.3 "Government Purchases in the Circular Flow". Like all the components of GDP, the production of goods and services for government agencies creates factor incomes for households.

Figure 6.3 Government Purchases in the Circular Flow

Purchases of goods and services by government agencies create demands on firms. As firms produce these goods and services, they create factor incomes for households.

Net Exports

Sales of a country’s goods and services to buyers in the rest of the world during a particular time period represent its exportsSales of a country’s goods and services to buyers in the rest of the world during a particular time period.. A purchase by a Japanese buyer of a Ford Taurus produced in the United States is a U.S. export. Exports also include such transactions as the purchase of accounting services from a New York accounting firm by a shipping line based in Hong Kong or the purchase of a ticket to Disney World by a tourist from Argentina. ImportsPurchases of foreign-produced goods and services by a country’s residents during a period. are purchases of foreign-produced goods and services by a country’s residents during a period. United States imports include such transactions as the purchase by Americans of cars produced in Japan or tomatoes grown in Mexico or a stay in a French hotel by a tourist from the United States. Subtracting imports from exports yields net exportsExports minus imports..

Equation 6.2

$$\text{Exports (}X\text{)}-\text{imports (}M\text{)}=\text{net exports (}{X}_n\text{)}$$

In 2011, foreign buyers purchased $2,087.5 billion worth of goods and services from the United States. In the same year, U.S. residents, firms, and government agencies purchased $2,664.4 billion worth of goods and services from foreign countries. The difference between these two figures, −$576.9 billion, represented the net exports of the U.S. economy in 2011. Net exports were negative because imports exceeded exports. Negative net exports constitute a trade deficitNegative net exports.. The amount of the deficit is the amount by which imports exceed exports. When exports exceed imports there is a trade surplusPositive net exports.. The magnitude of the surplus is the amount by which exports exceed imports.

The United States has recorded more deficits than surpluses since World War II, but the amounts have typically been relatively small, only a few billion dollars. The trade deficit began to soar, however, in the 1980s and again in the 2000s. We will examine the reasons for persistent trade deficits in another chapter. The rest of the world plays a key role in the domestic economy and, as we will see later in the book, there is nothing particularly good or bad about trade surpluses or deficits. Goods and services produced for export represent roughly 14% of GDP, and the goods and services the United States imports add significantly to our standard of living.

In the circular flow diagram in Figure 6.4 "Net Exports in the Circular Flow", net exports are shown with an arrow connecting firms to the rest of the world. The balance between the flows of exports and imports is net exports. When there is a trade surplus, net exports are positive and add spending to the circular flow. A trade deficit implies negative net exports; spending flows from firms to the rest of the world.

Figure 6.4 Net Exports in the Circular Flow

Net exports represent the balance between exports and imports. Net exports can be positive or negative. If they are positive, net export spending flows from the rest of the world to firms. If they are negative, spending flows from firms to the rest of the world.

The production of goods and services for personal consumption, private investment, government purchases, and net exports makes up a nation’s GDP. Firms produce these goods and services in response to demands from households (personal consumption), from other firms (private investment), from government agencies (government purchases), and from the rest of the world (net exports). All of this production creates factor income for households. Figure 6.5 "Spending in the Circular Flow Model" shows the circular flow model for all the spending flows we have discussed. Each flow is numbered for use in the exercise at the end of this section.

Figure 6.5 Spending in the Circular Flow Model

GDP equals the sum of production by firms of goods and services for personal consumption (1), private investment (2), government purchases (3), and net exports (4). The circular flow model shows these flows and shows that the production of goods and services generates factor incomes (5) to households.

The circular flow model identifies some of the forces at work in the economy, forces that we will be studying in later chapters. For example, an increase in any of the flows that place demands on firms (personal consumption, private investment, government purchases, and exports) will induce firms to expand their production. This effect is characteristic of the expansion phase of the business cycle. An increase in production will require firms to employ more factors of production, which will create more income for households. Households are likely to respond with more consumption, which will induce still more production, more income, and still more consumption. Similarly, a reduction in any of the demands placed on firms will lead to a reduction in output, a reduction in firms’ use of factors of production, a reduction in household incomes, a reduction in income, and so on. This sequence of events is characteristic of the contraction phase of the business cycle. Much of our work in macroeconomics will involve an analysis of the forces that prompt such changes in demand and an examination of the economy’s response to them.

Figure 6.6 "Components of GDP, 2011 in Billions of Dollars" shows the size of the components of GDP in 2011. We see that the production of goods and services for personal consumption accounted for about 70% of GDP. Imports exceeded exports, so net exports were negative.

Figure 6.6 Components of GDP, 2011 in Billions of Dollars

Consumption makes up the largest share of GDP. Net exports were negative in 2011. Total GDP—the sum of personal consumption, private investment, government purchases, and net exports—equaled $15,094.4 billion in 2011.

Source: Bureau of Economic Analysis, National Income and Product Accounts, Table 1.1.5 (revised February 29, 2012)

Final Goods and Value Added

GDP is the total value of all final goods and services produced during a particular period valued at prices in that period. That is not the same as the total value of all goods and services produced during a period. This distinction gives us another method of estimating GDP in terms of output.

Suppose, for example, that a logger cuts some trees and sells the logs to a sawmill. The mill makes lumber and sells it to a construction firm, which builds a house. The market price for the lumber includes the value of the logs; the price of the house includes the value of the lumber. If we try to estimate GDP by adding the value of the logs, the lumber, and the house, we would be counting the lumber twice and the logs three times. This problem is called “double counting,” and the economists who compute GDP seek to avoid it.

In the case of logs used for lumber and lumber produced for a house, GDP would include the value of the house. The lumber and the logs would not be counted as additional production because they are intermediate goods that were produced for use in building the house.

Another approach to estimating the value of final production is to estimate for each stage of production the value addedThe amount by which the value of a firm’s output exceeds the value of the goods and services the firm purchases from other firms., the amount by which the value of a firm’s output exceeds the value of the goods and services the firm purchases from other firms. Table 6.1 "Final Value and Value Added" illustrates the use of value added in the production of a house.

Suppose the logs produced by the logger are sold for $12,000 to a mill, and that the mill sells the lumber it produces from these logs for $25,000 to a construction firm. The construction firm uses the lumber to build a house, which it sells to a household for $125,000. (To simplify the example, we will ignore inputs other than lumber that are used to build the house.) The value of the final product, the house, is $125,000. The value added at each stage of production is estimated as follows:

1. The logger adds $12,000 by cutting the logs.
2. The mill adds $13,000 ($25,000 − $12,000) by cutting the logs into lumber.
3. The construction firm adds $100,000 ($125,000 − $25,000) by using the lumber to build a house.

The sum of values added at each stage ($12,000 + $13,000 + $100,000) equals the final value of the house, $125,000.

The value of an economy’s output in any period can thus be estimated in either of two ways. The values of final goods and services produced can be added directly, or the values added at each stage in the production process can be added. The Commerce Department uses both approaches in its estimate of the nation’s GDP.

GNP: An Alternative Measure of Output

While GDP represents the most commonly used measure of an economy’s output, economists sometimes use an alternative measure. Gross national product (GNP)The total value of final goods and services produced during a particular period with factors of production owned by the residents of a particular country. is the total value of final goods and services produced during a particular period with factors of production owned by the residents of a particular country.

The difference between GDP and GNP is a subtle one. The GDP of a country equals the value of final output produced within the borders of that country; the GNP of a country equals the value of final output produced using factors owned by residents of the country. Most production in a country employs factors of production owned by residents of that country, so the two measures overlap. Differences between the two measures emerge when production in one country employs factors of production owned by residents of other countries.

Suppose, for example, that a resident of Bellingham, Washington, owns and operates a watch repair shop across the Canadian–U.S. border in Victoria, British Columbia. The value of watch repair services produced at the shop would be counted as part of Canada’s GDP because they are produced in Canada. That value would not, however, be part of U.S. GDP. But, because the watch repair services were produced using capital and labor provided by a resident of the United States, they would be counted as part of GNP in the United States and not as part of GNP in Canada.

Because most production fits in both a country’s GDP as well as its GNP, there is seldom much difference between the two measures. The relationship between GDP and GNP is given by

In the third quarter of 2011, for example, GDP equaled $15,176.1 billion. We add income receipts of $792.2 billion earned by residents of the United States from the rest of the world and then subtract income payments of $524.9 billion that went from the United States to the rest of the world to get GNP of $15,443.4 billion for the third quarter of 2011. GNP is often used in international comparisons of income; we shall examine those later in this chapter.

Case in Point: The Spread of the Value Added Tax

Outside the United States, the value added tax (VAT) has become commonplace. Governments of more than 120 countries use it as their primary means of raising revenue. While the concept of the VAT originated in France in the 1920s, no country adopted it until after World War II. In 1948, France became the first country in the world to use the VAT. In 1967, Brazil became the first country in the Western Hemisphere to do so. The VAT spread to other western European and Latin American countries in the 1970s and 1980s and then to countries in the Asia/Pacific region, central European and former Soviet Union area, and Africa in the 1990s and early 2000s.

What is the VAT? It is equivalent to a sales tax on final goods and services but is collected at each stage of production.

Take the example given in Table 6.1 "Final Value and Value Added", which is a simplified illustration of a house built in three stages. If there were a sales tax of 10% on the house, the household buying it would pay $137,500, of which the construction firm would keep $125,000 of the total and turn $12,500 over to the government.

With a 10% VAT, the sawmill would pay the logger $13,200, of which the logger would keep $12,000 and turn $1,200 over to the government. The sawmill would sell the lumber to the construction firm for $27,500—keeping $26,200, which is the $25,000 for the lumber itself and $1,200 it already paid in tax. The government at this stage would get $1,300, the difference between the $2,500 the construction firm collected as tax and the $1,200 the sawmill already paid in tax to the logger at the previous stage. The household would pay the construction firm $137,500. Of that total, the construction firm would turn over to the government $10,000, which is the difference between the $12,500 it collected for the government in tax from the household and the $2,500 in tax that it already paid when it bought the lumber from the sawmill. The table below shows that in the end, the tax revenue generated by a 10% VAT is the same as that generated by a 10% tax on final sales.

Why bother to tax in stages instead of just on final sales? One reason is simply record keeping, since it may be difficult to determine in practice if any particular sale is the final one. In the example, the construction firm does not need to know if it is selling the house to a household or to some intermediary business.

Also, the VAT may lead to higher revenue collected. For example, even if somehow the household buying the house avoided paying the tax, the government would still have collected some tax revenue at earlier stages of production. With a tax on retail sales, it would have collected nothing. The VAT has another advantage from the point of view of government agencies. It has the appearance at each stage of taking a smaller share. The individual amounts collected are not as obvious to taxpayers as a sales tax might be.

Good	Price	Value Added	Tax Collected	− Tax Already Paid	= Value Added Tax
Logs	$12,000	$12,000	$1,200	− $0	= $1,200
Lumber	$25,000	$13,000	$2,500	− $1,200	= $1,300
House	$125,000	$100,000	$12,500	− $2,500	= $10,000
Total			$16,200	−$3,700	= $12,500

The Components of GDI

Employee compensation is the largest among the components of factor income. Factor income also includes profit, rent, and interest. In addition, GDI includes charges for depreciation and taxes associated with production. Depreciation and production-related taxes, such as sales taxes, make up part of the cost of producing goods and services and must be accounted for in estimating GDI. We will discuss each of these components of GDI next.

Tracing Income from the Economy to Households

We have seen that the production of goods and services generates income for households. Thus, the value of total output equals the value of total income in an economy. But we have also seen that our measure of total income, GDI, includes such things as depreciation and indirect business taxes that are not actually received by households. Households also receive some income, such as transfer payments, that does not count as part of GDP or GDI. Because the income households actually receive plays an important role in determining their consumption, it is useful to examine the relationship between a nation’s total output and the income households actually receive.

Table 6.3 "From GDP to Disposable Personal Income" traces the path we take in going from GDP to disposable personal incomeThe income households have available to spend on goods and services., which equals the income households have available to spend on goods and services. We first convert GDP to GNP and then subtract elements of GNP that do not represent income received by households and add payments such as transfer payments that households receive but do not earn in the production of GNP. Disposable personal income is either spent for personal consumption or saved by households.

Case in Point: The GDP–GDI Gap

GDP equals GDI; at least, that is the way it is supposed to work. But in an enormously complex economy, the measurement of these two variables inevitably goes awry. Estimates of the two are never quite equal. In recent years, the absolute value of the gap has been quite sizable, while in other years, it has been quite small. For example, for the years 2006 through 2010, GDI has differed from GDP by −242.3, −12.0, −2.4, 77.4, and 0.8 billion per year, respectively.

Although the gap seems large at times, it represents a remarkably small fraction of measured activity—around 1% or less. Of course, 1% of a big number is still a big number. But it is important to remember that, relative to the size of the economy, the gap between GDI and GDP is not large. The gap is listed as a “statistical discrepancy” in the Department of Commerce reporting of the two numbers.

Why does the gap exist? From an accounting point of view, it should not. The total value of final goods and services produced must be equal to the total value of income generated in that production. But output is measured from sales and inventory figures collected from just 10% of commercial establishments. Preliminary income figures are obtained from household surveys, but these represent a tiny fraction of households. More complete income data are provided by income tax returns, but these are available to the economists who estimate GDI only after a two- to four-year delay.

The Department of Commerce issues revisions of its GDP and GDI estimates as more complete data become available. With each revision, the gap between GDP and GDI estimates is significantly reduced.

While GDP and GDI figures cannot provide precise measures of economic activity, they come remarkably close. Indeed, given that the numbers come from entirely different sources, the fact that they come as close as they do provides an impressive check of the accuracy of the department’s estimates of GDP and GDI.

Measurement Problems in Real GDP

There are two measurement problems, other than those associated with adjusting for price level changes, in using real GDP to assess domestic economic performance.

Conceptual Problems with Real GDP

A second set of limitations of real GDP stems from problems inherent in the indicator itself. Real GDP measures market activity. Goods and services that are produced and exchanged in a market are counted; goods and services that are produced but that are not exchanged in markets are not.There are two exceptions to this rule. The value of food produced and consumed by farm households is counted in GDP. More important, an estimate of the rental values of owner-occupied homes is included. If a family rents a house, the rental payments are included in GDP. If a family lives in a house it owns, the Department of Commerce estimates what the house would rent for and then includes that rent in the GDP estimate, even though the house’s services were not exchanged in the marketplace.

International Comparisons of Real GDP and GNP

Real GDP or GNP estimates are often used in comparing economic performance among countries. In making such comparisons, it is important to keep in mind the general limitations to these measures of economic performance that we noted earlier. Further, countries use different methodologies for collecting and compiling data.

Three other issues are important in comparing real GDP or GNP for different countries: the adjustment of these figures for population, adjusting to a common currency, and the incorporation of nonmarket production.

In international comparisons of real GNP or real GDP, economists generally make comparisons not of real GNP or GDP but of per capita real GNP or GDPA country’s real GNP or GDP divided by its population., which equals a country’s real GNP or GDP divided by its population. For example, suppose Country A has a real GDP of about $4,000 billion and Country B has a real GDP of about $40 billion. We can conclude that Country A produced 100 times more goods and services than did Country B. But if Country A has 200 times as many people as Country B (for example, 200 million people in Country A and 1 million in Country B), then Country A’s per capita output will be half that of Country B ($20,000 versus $40,000 in this example).

Figure 6.7 "Comparing Per Capita Real GNP, 2010" compares per capita real GNP for 11 countries in 2010. It is based on data that uses a measure called “international dollars” in order to correct for differences in the purchasing power of $1 across countries. The data also attempt to adjust for nonmarket production (such as that of rural families that grow their own food, make their own clothing, and produce other household goods and services themselves).

Figure 6.7 Comparing Per Capita Real GNP, 2010

There is a huge gap between per capita income in one of the poorest countries in the world, the Democratic Republic of Congo, and wealthier nations such as the United States and Luxembourg.

Source: World Bank, World Development Indicators Online

The disparities in income are striking; Luxembourg, the country with the highest per capita real GNP, had an income level nearly 200 times greater than the Democratic Republic of Congo, the country with the lowest per capita real GNP.

What can we conclude about international comparisons in levels of GDP and GNP? Certainly we must be cautious. There are enormous difficulties in estimating any country’s total output. Comparing one country’s output to another presents additional challenges. But the fact that a task is difficult does not mean it is impossible. When the data suggest huge disparities in levels of GNP per capita, for example, we observe real differences in living standards.

Case in Point: Per Capita Real GDP and Olympic Medal Counts

In the popular lore, the Olympics provide an opportunity for the finest athletes in the world to compete with each other head-to-head on the basis of raw talent and hard work. And yet, contenders from Laos tend to finish last or close to it in almost any event in which they compete. One Laotian athlete garnered the unenviable record of having been the slowest entrant in the nearly half-century long history of the 20-kilometer walk. In contrast, U.S. athletes won 103 medals at the 2004 Athens Olympics and 110 medals at the 2008 Beijing Olympics. Why do Laotians fare so poorly and Americans so well, with athletes from other countries falling in between?

Economists Daniel K. N. Johnson and Ayfer Ali have been able to predict with astonishing accuracy the number of medals different countries will win on the basis of a handful of factors, including population, climate, political structure, and real per capita GDP. For example, they predicted that the United States would win 103 medals in Athens and that is precisely how many the United States won. They predicted 103 medals for the United States in Beijing; 110 were won. They did not expect the Laotians to win any medals in either Athens or Beijing, and that was indeed the outcome.

Johnson and Ali estimated that summer game participant nations average one more medal per additional $1,000 of per capita real GDP. With per capita real GDP in Laos less than the equivalent of $500 compared to per capita real GDP in the United States of about $38,000, the results for these two nations could be considered a foregone conclusion. According to Johnson and Ali, “High productive capacity or income per person displays an ability to pay the costs necessary to send athletes to the Games, and may also be associated with a higher quality of training and better equipment.” For example, a Laotian swimmer at Athens, Vilayphone Vongphachanh, had never practiced in an Olympic-size pool, and a runner, Sirivanh Ketavong, had worn the same running shoes for four years.

The good news is that as the per capita real GDP in some relatively poor countries has risen, the improved living standards have led to increased Olympic medal counts. China, for instance, won 28 medals in 1988 and 63 in 2004. As the host for the 2008 games, it won an impressive total of 100 medals.

While not a perfect measure of the well-being of people in a country, per capita real GDP does tell us about the opportunities available to the average citizen in a country. Americans would surely find it hard to imagine living at the level of consumption of the average Laotian. In The Progress Paradox: How Life Gets Better While People Feel Worse, essayist Gregg Easterbrook notes that a higher material standard of living is not associated with higher reported happiness. But, he concludes, the problems of prosperity seem less serious than those of poverty, and prosperity gives people and nations the means to address problems. The Olympic medal count for each nation strongly reflects its average standard of living and hence the opportunities available to its citizens.

Sources: Gregg Easterbrook, The Progress Paradox: How Life Gets Better While People Feel Worse (New York: Random House, 2003); Daniel K. N. Johnson and Ayfer Ali, “A Tale of Two Seasons: Participation and Medal Counts at the Summer and Winter Olympic Games,” Social Science Quarterly 84, no. 4 (December 2004): 974–93; David Wallechinsky, “Why I’ll Cheer for Laos,” Parade Magazine, August 8, 2004, p. 8.

The Slope of the Aggregate Demand Curve

We will use the implicit price deflator as our measure of the price level; the aggregate quantity of goods and services demanded is measured as real GDP. The table in Figure 7.1 "Aggregate Demand" gives values for each component of aggregate demand at each price level for a hypothetical economy. Various points on the aggregate demand curve are found by adding the values of these components at different price levels. The aggregate demand curve for the data given in the table is plotted on the graph in Figure 7.1 "Aggregate Demand". At point A, at a price level of 1.18, $11,800 billion worth of goods and services will be demanded; at point C, a reduction in the price level to 1.14 increases the quantity of goods and services demanded to $12,000 billion; and at point E, at a price level of 1.10, $12,200 billion will be demanded.

Figure 7.1 Aggregate Demand

An aggregate demand curve (AD) shows the relationship between the total quantity of output demanded (measured as real GDP) and the price level (measured as the implicit price deflator). At each price level, the total quantity of goods and services demanded is the sum of the components of real GDP, as shown in the table. There is a negative relationship between the price level and the total quantity of goods and services demanded, all other things unchanged.

The negative slope of the aggregate demand curve suggests that it behaves in the same manner as an ordinary demand curve. But we cannot apply the reasoning we use to explain downward-sloping demand curves in individual markets to explain the downward-sloping aggregate demand curve. There are two reasons for a negative relationship between price and quantity demanded in individual markets. First, a lower price induces people to substitute more of the good whose price has fallen for other goods, increasing the quantity demanded. Second, the lower price creates a higher real income. This normally increases quantity demanded further.

Neither of these effects is relevant to a change in prices in the aggregate. When we are dealing with the average of all prices—the price level—we can no longer say that a fall in prices will induce a change in relative prices that will lead consumers to buy more of the goods and services whose prices have fallen and less of the goods and services whose prices have not fallen. The price of corn may have fallen, but the prices of wheat, sugar, tractors, steel, and most other goods or services produced in the economy are likely to have fallen as well.

Furthermore, a reduction in the price level means that it is not just the prices consumers pay that are falling. It means the prices people receive—their wages, the rents they may charge as landlords, the interest rates they earn—are likely to be falling as well. A falling price level means that goods and services are cheaper, but incomes are lower, too. There is no reason to expect that a change in real income will boost the quantity of goods and services demanded—indeed, no change in real income would occur. If nominal incomes and prices all fall by 10%, for example, real incomes do not change.

Why, then, does the aggregate demand curve slope downward? One reason for the downward slope of the aggregate demand curve lies in the relationship between real wealth (the stocks, bonds, and other assets that people have accumulated) and consumption (one of the four components of aggregate demand). When the price level falls, the real value of wealth increases—it packs more purchasing power. For example, if the price level falls by 25%, then $10,000 of wealth could purchase more goods and services than it would have if the price level had not fallen. An increase in wealth will induce people to increase their consumption. The consumption component of aggregate demand will thus be greater at lower price levels than at higher price levels. The tendency for a change in the price level to affect real wealth and thus alter consumption is called the wealth effectThe tendency for a change in the price level to affect real wealth and thus alter consumption.; it suggests a negative relationship between the price level and the real value of consumption spending.

A second reason the aggregate demand curve slopes downward lies in the relationship between interest rates and investment. A lower price level lowers the demand for money, because less money is required to buy a given quantity of goods. What economists mean by money demand will be explained in more detail in a later chapter. But, as we learned in studying demand and supply, a reduction in the demand for something, all other things unchanged, lowers its price. In this case, the “something” is money and its price is the interest rate. A lower price level thus reduces interest rates. Lower interest rates make borrowing by firms to build factories or buy equipment and other capital more attractive. A lower interest rate means lower mortgage payments, which tends to increase investment in residential houses. Investment thus rises when the price level falls. The tendency for a change in the price level to affect the interest rate and thus to affect the quantity of investment demanded is called the interest rate effectThe tendency for a change in the price level to affect the interest rate and thus to affect the quantity of investment demanded.. John Maynard Keynes, a British economist whose analysis of the Great Depression and what to do about it led to the birth of modern macroeconomics, emphasized this effect. For this reason, the interest rate effect is sometimes called the Keynes effect.

A third reason for the rise in the total quantity of goods and services demanded as the price level falls can be found in changes in the net export component of aggregate demand. All other things unchanged, a lower price level in an economy reduces the prices of its goods and services relative to foreign-produced goods and services. A lower price level makes that economy’s goods more attractive to foreign buyers, increasing exports. It will also make foreign-produced goods and services less attractive to the economy’s buyers, reducing imports. The result is an increase in net exports. The international trade effectThe tendency for a change in the price level to affect net exports. is the tendency for a change in the price level to affect net exports.

Taken together, then, a fall in the price level means that the quantities of consumption, investment, and net export components of aggregate demand may all rise. Since government purchases are determined through a political process, we assume there is no causal link between the price level and the real volume of government purchases. Therefore, this component of GDP does not contribute to the downward slope of the curve.

In general, a change in the price level, with all other determinants of aggregate demand unchanged, causes a movement along the aggregate demand curve. A movement along an aggregate demand curve is a change in the aggregate quantity of goods and services demandedMovement along an aggregate demand curve.. A movement from point A to point B on the aggregate demand curve in Figure 7.1 "Aggregate Demand" is an example. Such a change is a response to a change in the price level.

Notice that the axes of the aggregate demand curve graph are drawn with a break near the origin to remind us that the plotted values reflect a relatively narrow range of changes in real GDP and the price level. We do not know what might happen if the price level or output for an entire economy approached zero. Such a phenomenon has never been observed.

Changes in Aggregate Demand

Aggregate demand changes in response to a change in any of its components. An increase in the total quantity of consumer goods and services demanded at every price level, for example, would shift the aggregate demand curve to the right. A change in the aggregate quantity of goods and services demanded at every price level is a change in aggregate demandChange in the aggregate quantity of goods and services demanded at every price level., which shifts the aggregate demand curve. Increases and decreases in aggregate demand are shown in Figure 7.2 "Changes in Aggregate Demand".

Figure 7.2 Changes in Aggregate Demand

An increase in consumption, investment, government purchases, or net exports shifts the aggregate demand curve AD₁ to the right as shown in Panel (a). A reduction in one of the components of aggregate demand shifts the curve to the left, as shown in Panel (b).

What factors might cause the aggregate demand curve to shift? Each of the components of aggregate demand is a possible aggregate demand shifter. We shall look at some of the events that can trigger changes in the components of aggregate demand and thus shift the aggregate demand curve.

The Multiplier

A change in any component of aggregate demand shifts the aggregate demand curve. Generally, the aggregate demand curve shifts by more than the amount by which the component initially causing it to shift changes.

Suppose that net exports increase due to an increase in foreign incomes. As foreign demand for domestically made products rises, a country’s firms will hire additional workers or perhaps increase the average number of hours that their employees work. In either case, incomes will rise, and higher incomes will lead to an increase in consumption. Taking into account these other increases in the components of aggregate demand, the aggregate demand curve will shift by more than the initial shift caused by the initial increase in net exports.

The multiplierThe ratio of the change in the quantity of real GDP demanded at each price level to the initial change in one or more components of aggregate demand that produced it. is the ratio of the change in the quantity of real GDP demanded at each price level to the initial change in one or more components of aggregate demand that produced it:

Equation 7.1

$$\text{Multiplier}=\frac{\Delta \text{ (real GDP demanded at each price level)}}{\text{initial }\Delta \text{ (component of }\mathit{AD}\text{)}}$$

We use the capital Greek letter delta (Δ) to mean “change in.” In the aggregate demand–aggregate supply model presented in this chapter, it is the number by which we multiply an initial change in aggregate demand to obtain the amount by which the aggregate demand curve shifts as a result of the initial change. In other words, we can use Equation 7.1 to solve for the change in real GDP demanded at each price level:

Equation 7.2

$$\Delta \text{ (real GDP demanded at each price level)}=\text{multiplier}\times \text{initial }\Delta \text{ (component of }\mathit{AD}\text{)}$$

Suppose that the initial increase in net exports is $100 billion and that the initial $100-billion increase generates additional consumption of $100 billion at each price level. In Panel (a) of Figure 7.3 "The Multiplier", the aggregate demand curve shifts to the right by $200 billion—the amount of the initial increase in net exports times the multiplier of 2. We obtained the value for the multiplier in this example by plugging $200 billion (the initial $100-billion increase in net exports plus the $100-billion increase that it generated in consumption) into the numerator of Equation 7.1 and $100 billion into the denominator. Similarly, a decrease in net exports of $100 billion leads to a decrease in aggregate demand of $200 billion at each price level, as shown in Panel (b).

Figure 7.3 The Multiplier

A change in one component of aggregate demand shifts the aggregate demand curve by more than the initial change. In Panel (a), an initial increase of $100 billion of net exports shifts the aggregate demand curve to the right by $200 billion at each price level. In Panel (b), a decrease of net exports of $100 billion shifts the aggregate demand curve to the left by $200 billion. In this example, the multiplier is 2.

Key Takeaways

• Potential output is the level of output an economy can achieve when labor is employed at its natural level. When an economy fails to produce at its potential, the government or the central bank may try to push the economy toward its potential.
• The aggregate demand curve represents the total of consumption, investment, government purchases, and net exports at each price level in any period. It slopes downward because of the wealth effect on consumption, the interest rate effect on investment, and the international trade effect on net exports.
• The aggregate demand curve shifts when the quantity of real GDP demanded at each price level changes.
• The multiplier is the number by which we multiply an initial change in aggregate demand to obtain the amount by which the aggregate demand curve shifts at each price level as a result of the initial change.

Try It!

Explain the effect of each of the following on the aggregate demand curve for the United States:

1. A decrease in consumer optimism
2. An increase in real GDP in the countries that buy U.S. exports
3. An increase in the price level
4. An increase in government spending on highways

Case in Point: The Multiplied Economic Impact of SARS on China’s Economy

Severe Acute Respiratory Syndrome (SARS), an atypical pneumonia-like disease, broke onto the world scene in late 2002. In March 2003, the World Health Organization (WHO) issued its first worldwide alert and a month later its first travel advisory, which recommended that travelers avoid Hong Kong and the southern province of China, Guangdong. Over the next few months, additional travel advisories were issued for other parts of China, Taiwan, and briefly for Toronto, Canada. By the end of June, all WHO travel advisories had been removed.

To estimate the overall impact of SARS on the Chinese economy in 2003, economists Wen Hai, Zhong Zhao, and Jian Want of Peking University’s China Center for Economic Research conducted a survey of Beijing’s tourism industry in April 2003. Based on findings from the Beijing area, they projected the tourism sector of China as a whole would lose $16.8 billion—of which $10.8 billion came from an approximate 50% reduction in foreign tourist revenue and $6 billion from curtailed domestic tourism, as holiday celebrations were cancelled and domestic travel restrictions imposed.

To figure out the total impact of SARS on China’s economy, they argued that the multiplier for tourism revenue in China is between 2 and 3. Since the SARS outbreak only began to have a major economic impact after March, they assumed a smaller multiplier of 1.5 for all of 2003. They thus predicted that the Chinese economy would be $25.3 billion smaller in 2003 as a result of SARS.

Source: Wen Hai, Zhong Zhao, and Jian Wan, “The Short-Term Impact of SARS on the Chinese Economy,” Asian Economic Papers 3, no. 1 (Winter 2004): 57–61.

Answer to Try It! Problem

1. A decline in consumer optimism would cause the aggregate demand curve to shift to the left. If consumers are more pessimistic about the future, they are likely to cut purchases, especially of major items.
2. An increase in the real GDP of other countries would increase the demand for U.S. exports and cause the aggregate demand curve to shift to the right. Higher incomes in other countries will make consumers in those countries more willing and able to buy U.S. goods.
3. An increase in the price level corresponds to a movement up along the unchanged aggregate demand curve. At the higher price level, the consumption, investment, and net export components of aggregate demand will all fall; that is, there will be a reduction in the total quantity of goods and services demanded, but not a shift of the aggregate demand curve itself.
4. An increase in government spending on highways means an increase in government purchases. The aggregate demand curve would shift to the right.

The Long Run

As we saw in a previous chapter, the natural level of employment occurs where the real wage adjusts so that the quantity of labor demanded equals the quantity of labor supplied. When the economy achieves its natural level of employment, it achieves its potential level of output. We will see that real GDP eventually moves to potential, because all wages and prices are assumed to be flexible in the long run.

Long-Run Aggregate Supply

The long-run aggregate supply (LRAS) curveA graphical representation that relates the level of output produced by firms to the price level in the long run. relates the level of output produced by firms to the price level in the long run. In Panel (b) of Figure 7.4 "Natural Employment and Long-Run Aggregate Supply", the long-run aggregate supply curve is a vertical line at the economy’s potential level of output. There is a single real wage at which employment reaches its natural level. In Panel (a) of Figure 7.4 "Natural Employment and Long-Run Aggregate Supply", only a real wage of ω_e generates natural employment L_e. The economy could, however, achieve this real wage with any of an infinitely large set of nominal wage and price-level combinations. Suppose, for example, that the equilibrium real wage (the ratio of wages to the price level) is 1.5. We could have that with a nominal wage level of 1.5 and a price level of 1.0, a nominal wage level of 1.65 and a price level of 1.1, a nominal wage level of 3.0 and a price level of 2.0, and so on.

Figure 7.4 Natural Employment and Long-Run Aggregate Supply

When the economy achieves its natural level of employment, as shown in Panel (a) at the intersection of the demand and supply curves for labor, it achieves its potential output, as shown in Panel (b) by the vertical long-run aggregate supply curve LRAS at Y_P.

In Panel (b) we see price levels ranging from P₁ to P₄. Higher price levels would require higher nominal wages to create a real wage of ω_e, and flexible nominal wages would achieve that in the long run.

In the long run, then, the economy can achieve its natural level of employment and potential output at any price level. This conclusion gives us our long-run aggregate supply curve. With only one level of output at any price level, the long-run aggregate supply curve is a vertical line at the economy’s potential level of output of Y_P.

Equilibrium Levels of Price and Output in the Long Run

The intersection of the economy’s aggregate demand curve and the long-run aggregate supply curve determines its equilibrium real GDP and price level in the long run. Figure 7.5 "Long-Run Equilibrium" depicts an economy in long-run equilibrium. With aggregate demand at AD₁ and the long-run aggregate supply curve as shown, real GDP is $12,000 billion per year and the price level is 1.14. If aggregate demand increases to AD₂, long-run equilibrium will be reestablished at real GDP of $12,000 billion per year, but at a higher price level of 1.18. If aggregate demand decreases to AD₃, long-run equilibrium will still be at real GDP of $12,000 billion per year, but with the now lower price level of 1.10.

Figure 7.5 Long-Run Equilibrium

Long-run equilibrium occurs at the intersection of the aggregate demand curve and the long-run aggregate supply curve. For the three aggregate demand curves shown, long-run equilibrium occurs at three different price levels, but always at an output level of $12,000 billion per year, which corresponds to potential output.

The Short Run

Analysis of the macroeconomy in the short run—a period in which stickiness of wages and prices may prevent the economy from operating at potential output—helps explain how deviations of real GDP from potential output can and do occur. We will explore the effects of changes in aggregate demand and in short-run aggregate supply in this section.

Short-Run Aggregate Supply

Figure 7.6 Deriving the Short-Run Aggregate Supply Curve

The economy shown here is in long-run equilibrium at the intersection of AD₁ with the long-run aggregate supply curve. If aggregate demand increases to AD₂, in the short run, both real GDP and the price level rise. If aggregate demand decreases to AD₃, in the short run, both real GDP and the price level fall. A line drawn through points A, B, and C traces out the short-run aggregate supply curve SRAS.

The model of aggregate demand and long-run aggregate supply predicts that the economy will eventually move toward its potential output. To see how nominal wage and price stickiness can cause real GDP to be either above or below potential in the short run, consider the response of the economy to a change in aggregate demand. Figure 7.6 "Deriving the Short-Run Aggregate Supply Curve" shows an economy that has been operating at potential output of $12,000 billion and a price level of 1.14. This occurs at the intersection of AD₁ with the long-run aggregate supply curve at point B. Now suppose that the aggregate demand curve shifts to the right (to AD₂). This could occur as a result of an increase in exports. (The shift from AD₁ to AD₂ includes the multiplied effect of the increase in exports.) At the price level of 1.14, there is now excess demand and pressure on prices to rise. If all prices in the economy adjusted quickly, the economy would quickly settle at potential output of $12,000 billion, but at a higher price level (1.18 in this case).

Is it possible to expand output above potential? Yes. It may be the case, for example, that some people who were in the labor force but were frictionally or structurally unemployed find work because of the ease of getting jobs at the going nominal wage in such an environment. The result is an economy operating at point A in Figure 7.6 "Deriving the Short-Run Aggregate Supply Curve" at a higher price level and with output temporarily above potential.

Consider next the effect of a reduction in aggregate demand (to AD₃), possibly due to a reduction in investment. As the price level starts to fall, output also falls. The economy finds itself at a price level–output combination at which real GDP is below potential, at point C. Again, price stickiness is to blame. The prices firms receive are falling with the reduction in demand. Without corresponding reductions in nominal wages, there will be an increase in the real wage. Firms will employ less labor and produce less output.

By examining what happens as aggregate demand shifts over a period when price adjustment is incomplete, we can trace out the short-run aggregate supply curve by drawing a line through points A, B, and C. The short-run aggregate supply (SRAS) curveA graphical representation of the relationship between production and the price level in the short run. is a graphical representation of the relationship between production and the price level in the short run. Among the factors held constant in drawing a short-run aggregate supply curve are the capital stock, the stock of natural resources, the level of technology, and the prices of factors of production.

A change in the price level produces a change in the aggregate quantity of goods and services suppliedMovement along the short-run aggregate supply curve. and is illustrated by the movement along the short-run aggregate supply curve. This occurs between points A, B, and C in Figure 7.6 "Deriving the Short-Run Aggregate Supply Curve".

A change in the quantity of goods and services supplied at every price level in the short run is a change in short-run aggregate supplyA change in the aggregate quantity of goods and services supplied at every price level in the short run.. Changes in the factors held constant in drawing the short-run aggregate supply curve shift the curve. (These factors may also shift the long-run aggregate supply curve; we will discuss them along with other determinants of long-run aggregate supply in the next chapter.)

One type of event that would shift the short-run aggregate supply curve is an increase in the price of a natural resource such as oil. An increase in the price of natural resources or any other factor of production, all other things unchanged, raises the cost of production and leads to a reduction in short-run aggregate supply. In Panel (a) of Figure 7.7 "Changes in Short-Run Aggregate Supply", SRAS₁ shifts leftward to SRAS₂. A decrease in the price of a natural resource would lower the cost of production and, other things unchanged, would allow greater production from the economy’s stock of resources and would shift the short-run aggregate supply curve to the right; such a shift is shown in Panel (b) by a shift from SRAS₁ to SRAS₃.

Figure 7.7 Changes in Short-Run Aggregate Supply

A reduction in short-run aggregate supply shifts the curve from SRAS₁ to SRAS₂ in Panel (a). An increase shifts it to the right to SRAS₃, as shown in Panel (b).

Equilibrium Levels of Price and Output in the Short Run

To illustrate how we will use the model of aggregate demand and aggregate supply, let us examine the impact of two events: an increase in the cost of health care and an increase in government purchases. The first reduces short-run aggregate supply; the second increases aggregate demand. Both events change equilibrium real GDP and the price level in the short run.

A Change in the Cost of Health Care

In the United States, most people receive health insurance for themselves and their families through their employers. In fact, it is quite common for employers to pay a large percentage of employees’ health insurance premiums, and this benefit is often written into labor contracts. As the cost of health care has gone up over time, firms have had to pay higher and higher health insurance premiums. With nominal wages fixed in the short run, an increase in health insurance premiums paid by firms raises the cost of employing each worker. It affects the cost of production in the same way that higher wages would. The result of higher health insurance premiums is that firms will choose to employ fewer workers.

Suppose the economy is operating initially at the short-run equilibrium at the intersection of AD₁ and SRAS₁, with a real GDP of Y₁ and a price level of P₁, as shown in Figure 7.8 "An Increase in Health Insurance Premiums Paid by Firms". This is the initial equilibrium price and output in the short run. The increase in labor cost shifts the short-run aggregate supply curve to SRAS₂. The price level rises to P₂ and real GDP falls to Y₂.

Figure 7.8 An Increase in Health Insurance Premiums Paid by Firms

An increase in health insurance premiums paid by firms increases labor costs, reducing short-run aggregate supply from SRAS₁ to SRAS₂. The price level rises from P₁ to P₂ and output falls from Y₁ to Y₂.

A reduction in health insurance premiums would have the opposite effect. There would be a shift to the right in the short-run aggregate supply curve with pressure on the price level to fall and real GDP to rise.

A Change in Government Purchases

Suppose the federal government increases its spending for highway construction. This circumstance leads to an increase in U.S. government purchases and an increase in aggregate demand.

Assuming no other changes affect aggregate demand, the increase in government purchases shifts the aggregate demand curve by a multiplied amount of the initial increase in government purchases to AD₂ in Figure 7.9 "An Increase in Government Purchases". Real GDP rises from Y₁ to Y₂, while the price level rises from P₁ to P₂. Notice that the increase in real GDP is less than it would have been if the price level had not risen.

Figure 7.9 An Increase in Government Purchases

An increase in government purchases boosts aggregate demand from AD₁ to AD₂. Short-run equilibrium is at the intersection of AD₂ and the short-run aggregate supply curve SRAS₁. The price level rises to P₂ and real GDP rises to Y₂.

In contrast, a reduction in government purchases would reduce aggregate demand. The aggregate demand curve shifts to the left, putting pressure on both the price level and real GDP to fall.

In the short run, real GDP and the price level are determined by the intersection of the aggregate demand and short-run aggregate supply curves. Recall, however, that the short run is a period in which sticky prices may prevent the economy from reaching its natural level of employment and potential output. In the next section, we will see how the model adjusts to move the economy to long-run equilibrium and what, if anything, can be done to steer the economy toward the natural level of employment and potential output.

Key Takeaways

• The short run in macroeconomics is a period in which wages and some other prices are sticky. The long run is a period in which full wage and price flexibility, and market adjustment, has been achieved, so that the economy is at the natural level of employment and potential output.
• The long-run aggregate supply curve is a vertical line at the potential level of output. The intersection of the economy’s aggregate demand and long-run aggregate supply curves determines its equilibrium real GDP and price level in the long run.
• The short-run aggregate supply curve is an upward-sloping curve that shows the quantity of total output that will be produced at each price level in the short run. Wage and price stickiness account for the short-run aggregate supply curve’s upward slope.
• Changes in prices of factors of production shift the short-run aggregate supply curve. In addition, changes in the capital stock, the stock of natural resources, and the level of technology can also cause the short-run aggregate supply curve to shift.
• In the short run, the equilibrium price level and the equilibrium level of total output are determined by the intersection of the aggregate demand and the short-run aggregate supply curves. In the short run, output can be either below or above potential output.

Try It!

The tools we have covered in this section can be used to understand the Great Depression of the 1930s. We know that investment and consumption began falling in late 1929. The reductions were reinforced by plunges in net exports and government purchases over the next four years. In addition, nominal wages plunged 26% between 1929 and 1933. We also know that real GDP in 1933 was 30% below real GDP in 1929. Use the tools of aggregate demand and short-run aggregate supply to graph and explain what happened to the economy between 1929 and 1933.

Case in Point: The U.S. Recession of 2001

What were the causes of the U.S. recession of 2001? Economist Kevin Kliesen of the Federal Reserve Bank of St. Louis points to four factors that, taken together, shifted the aggregate demand curve to the left and kept it there for a long enough period to keep real GDP falling for about nine months. They were the fall in stock market prices, the decrease in business investment both for computers and software and in structures, the decline in the real value of exports, and the aftermath of 9/11. Notable exceptions to this list of culprits were the behavior of consumer spending during the period and new residential housing, which falls into the investment category.

During the expansion in the late 1990s, a surging stock market probably made it easier for firms to raise funding for investment in both structures and information technology. Even though the stock market bubble burst well before the actual recession, the continuation of projects already underway delayed the decline in the investment component of GDP. Also, spending for information technology was probably prolonged as firms dealt with Y2K computing issues, that is, computer problems associated with the change in the date from 1999 to 2000. Most computers used only two digits to indicate the year, and when the year changed from ’99 to ’00, computers did not know how to interpret the change, and extensive reprogramming of computers was required.

Real exports fell during the recession because (1) the dollar was strong during the period and (2) real GDP growth in the rest of the world fell almost 5% from 2000 to 2001.

Then, the terrorist attacks of 9/11, which literally shut down transportation and financial markets for several days, may have prolonged these negative tendencies just long enough to turn what might otherwise have been a mild decline into enough of a downtown to qualify the period as a recession.

During this period the measured price level was essentially stable—with the implicit price deflator rising by less than 1%. Thus, while the aggregate demand curve shifted left as a result of all the reasons given above, there was also a leftward shift in the short-run aggregate supply curve.

Source: Kevin L. Kliesen, “The 2001 Recession: How Was It Different and What Developments May Have Caused It?,” The Federal Reserve Bank of St. Louis Review, September/October 2003, 23–37.

Answer to Try It! Problem

All components of aggregate demand (consumption, investment, government purchases, and net exports) declined between 1929 and 1933. Thus the aggregate demand curve shifted markedly to the left, moving from AD₁₉₂₉ to AD₁₉₃₃. The reduction in nominal wages corresponds to an increase in short-run aggregate supply from SRAS₁₉₂₉ to SRAS₁₉₃₃. Since real GDP in 1933 was less than real GDP in 1929, we know that the movement in the aggregate demand curve was greater than that of the short-run aggregate supply curve.

Recessionary and Inflationary Gaps

At any time, real GDP and the price level are determined by the intersection of the aggregate demand and short-run aggregate supply curves. If employment is below the natural level of employment, real GDP will be below potential. The aggregate demand and short-run aggregate supply curves will intersect to the left of the long-run aggregate supply curve.

Suppose an economy’s natural level of employment is L_e, shown in Panel (a) of Figure 7.10 "A Recessionary Gap". This level of employment is achieved at a real wage of ω_e. Suppose, however, that the initial real wage ω₁ exceeds this equilibrium value. Employment at L₁ falls short of the natural level. A lower level of employment produces a lower level of output; the aggregate demand and short-run aggregate supply curves, AD and SRAS, intersect to the left of the long-run aggregate supply curve LRAS in Panel (b). The gap between the level of real GDP and potential output, when real GDP is less than potential, is called a recessionary gapThe gap between the level of real GDP and potential output, when real GDP is less than potential..

Figure 7.10 A Recessionary Gap

If employment is below the natural level, as shown in Panel (a), then output must be below potential. Panel (b) shows the recessionary gap Y_P − Y₁, which occurs when the aggregate demand curve AD and the short-run aggregate supply curve SRAS intersect to the left of the long-run aggregate supply curve LRAS.

Just as employment can fall short of its natural level, it can also exceed it. If employment is greater than its natural level, real GDP will also be greater than its potential level. Figure 7.11 "An Inflationary Gap" shows an economy with a natural level of employment of L_e in Panel (a) and potential output of Y_P in Panel (b). If the real wage ω₁ is less than the equilibrium real wage ω_e, then employment L₁ will exceed the natural level. As a result, real GDP, Y₁, exceeds potential. The gap between the level of real GDP and potential output, when real GDP is greater than potential, is called an inflationary gapThe gap between the level of real GDP and potential output, when real GDP is greater than potential.. In Panel (b), the inflationary gap equals Y₁ − Y_P.

Figure 7.11 An Inflationary Gap

Panel (a) shows that if employment is above the natural level, then output must be above potential. The inflationary gap, shown in Panel (b), equals Y₁ − Y_P. The aggregate demand curve AD and the short-run aggregate supply curve SRAS intersect to the right of the long-run aggregate supply curve LRAS.

Restoring Long-Run Macroeconomic Equilibrium

We have already seen that the aggregate demand curve shifts in response to a change in consumption, investment, government purchases, or net exports. The short-run aggregate supply curve shifts in response to changes in the prices of factors of production, the quantities of factors of production available, or technology. Now we will see how the economy responds to a shift in aggregate demand or short-run aggregate supply using two examples presented earlier: a change in government purchases and a change in health-care costs. By returning to these examples, we will be able to distinguish the long-run response from the short-run response.

A Shift in Aggregate Demand: An Increase in Government Purchases

Suppose an economy is initially in equilibrium at potential output YP as in Figure 7.12 "Long-Run Adjustment to an Inflationary Gap". Because the economy is operating at its potential, the labor market must be in equilibrium; the quantities of labor demanded and supplied are equal.

Figure 7.12 Long-Run Adjustment to an Inflationary Gap

An increase in aggregate demand to AD₂ boosts real GDP to Y₂ and the price level to P₂, creating an inflationary gap of Y₂ − Y_P. In the long run, as price and nominal wages increase, the short-run aggregate supply curve moves to SRAS₂. Real GDP returns to potential.

Now suppose aggregate demand increases because one or more of its components (consumption, investment, government purchases, and net exports) has increased at each price level. For example, suppose government purchases increase. The aggregate demand curve shifts from AD₁ to AD₂ in Figure 7.12 "Long-Run Adjustment to an Inflationary Gap". That will increase real GDP to Y₂ and force the price level up to P₂ in the short run. The higher price level, combined with a fixed nominal wage, results in a lower real wage. Firms employ more workers to supply the increased output.

The economy’s new production level Y₂ exceeds potential output. Employment exceeds its natural level. The economy with output of Y₂ and price level of P₂ is only in short-run equilibrium; there is an inflationary gap equal to the difference between Y₂ and Y_P. Because real GDP is above potential, there will be pressure on prices to rise further.

Ultimately, the nominal wage will rise as workers seek to restore their lost purchasing power. As the nominal wage rises, the short-run aggregate supply curve will begin shifting to the left. It will continue to shift as long as the nominal wage rises, and the nominal wage will rise as long as there is an inflationary gap. These shifts in short-run aggregate supply, however, will reduce real GDP and thus begin to close this gap. When the short-run aggregate supply curve reaches SRAS₂, the economy will have returned to its potential output, and employment will have returned to its natural level. These adjustments will close the inflationary gap.

A Shift in Short-Run Aggregate Supply: An Increase in the Cost of Health Care

Again suppose, with an aggregate demand curve at AD₁ and a short-run aggregate supply at SRAS₁, an economy is initially in equilibrium at its potential output Y_P, at a price level of P₁, as shown in Figure 7.13 "Long-Run Adjustment to a Recessionary Gap". Now suppose that the short-run aggregate supply curve shifts owing to a rise in the cost of health care. As we explained earlier, because health insurance premiums are paid primarily by firms for their workers, an increase in premiums raises the cost of production and causes a reduction in the short-run aggregate supply curve from SRAS₁ to SRAS₂.

Figure 7.13 Long-Run Adjustment to a Recessionary Gap

A decrease in aggregate supply from SRAS₁ to SRAS₂ reduces real GDP to Y₂ and raises the price level to P₂, creating a recessionary gap of Y_P − Y₂. In the long run, as prices and nominal wages decrease, the short-run aggregate supply curve moves back to SRAS₁ and real GDP returns to potential.

As a result, the price level rises to P₂ and real GDP falls to Y₂. The economy now has a recessionary gap equal to the difference between Y_P and Y₂. Notice that this situation is particularly disagreeable, because both unemployment and the price level rose.

With real GDP below potential, though, there will eventually be pressure on the price level to fall. Increased unemployment also puts pressure on nominal wages to fall. In the long run, the short-run aggregate supply curve shifts back to SRAS₁. In this case, real GDP returns to potential at Y_P, the price level falls back to P₁, and employment returns to its natural level. These adjustments will close the recessionary gap.

How sticky prices and nominal wages are will determine the time it takes for the economy to return to potential. People often expect the government or the central bank to respond in some way to try to close gaps. This issue is addressed next.

Gaps and Public Policy

If the economy faces a gap, how do we get from that situation to potential output?

Gaps present us with two alternatives. First, we can do nothing. In the long run, real wages will adjust to the equilibrium level, employment will move to its natural level, and real GDP will move to its potential. Second, we can do something. Faced with a recessionary or an inflationary gap, policy makers can undertake policies aimed at shifting the aggregate demand or short-run aggregate supply curves in a way that moves the economy to its potential. A policy choice to take no action to try to close a recessionary or an inflationary gap, but to allow the economy to adjust on its own to its potential output, is a nonintervention policyA policy choice to take no action to try to close a recessionary or an inflationary gap, but to allow the economy to adjust on its own to its potential output.. A policy in which the government or central bank acts to move the economy to its potential output is called a stabilization policyA policy in which the government or central bank acts to move the economy to its potential output..

Nonintervention or Expansionary Policy?

Figure 7.14 "Alternatives in Closing a Recessionary Gap" illustrates the alternatives for closing a recessionary gap. In both panels, the economy starts with a real GDP of Y₁ and a price level of P₁. There is a recessionary gap equal to Y_P − Y₁. In Panel (a), the economy closes the gap through a process of self-correction. Real and nominal wages will fall as long as employment remains below the natural level. Lower nominal wages shift the short-run aggregate supply curve. The process is a gradual one, however, given the stickiness of nominal wages, but after a series of shifts in the short-run aggregate supply curve, the economy moves toward equilibrium at a price level of P₂ and its potential output of Y_P.

Figure 7.14 Alternatives in Closing a Recessionary Gap

Panel (a) illustrates a gradual closing of a recessionary gap. Under a nonintervention policy, short-run aggregate supply shifts from SRAS₁ to SRAS₂. Panel (b) shows the effects of expansionary policy acting on aggregate demand to close the gap.

Panel (b) illustrates the stabilization alternative. Faced with an economy operating below its potential, public officials act to stimulate aggregate demand. For example, the government can increase government purchases of goods and services or cut taxes. Tax cuts leave people with more after-tax income to spend, boost their consumption, and increase aggregate demand. As AD₁ shifts to AD₂ in Panel (b) of Figure 7.14 "Alternatives in Closing a Recessionary Gap", the economy achieves output of Y_P, but at a higher price level, P₃. A stabilization policy designed to increase real GDP is known as an expansionary policyA stabilization policy designed to increase real GDP..

Nonintervention or Contractionary Policy?

Figure 7.15 "Alternatives in Closing an Inflationary Gap" illustrates the alternatives for closing an inflationary gap. Employment in an economy with an inflationary gap exceeds its natural level—the quantity of labor demanded exceeds the long-run supply of labor. A nonintervention policy would rely on nominal wages to rise in response to the shortage of labor. As nominal wages rise, the short-run aggregate supply curve begins to shift, as shown in Panel (a), bringing the economy to its potential output when it reaches SRAS₂ and P₂.

Figure 7.15 Alternatives in Closing an Inflationary Gap

Panel (a) illustrates a gradual closing of an inflationary gap. Under a nonintervention policy, short-run aggregate supply shifts from SRAS₁ to SRAS₂. Panel (b) shows the effects of contractionary policy to reduce aggregate demand from AD₁ to AD₂ in order to close the gap.

A stabilization policy that reduces the level of GDP is a contractionary policyA stabilization policy designed to reduce real GDP.. Such a policy would aim at shifting the aggregate demand curve from AD₁ to AD₂ to close the gap, as shown in Panel (b). A policy to shift the aggregate demand curve to the left would return real GDP to its potential at a price level of P₃.

For both kinds of gaps, a combination of letting market forces in the economy close part of the gap and of using stabilization policy to close the rest of the gap is also an option. Later chapters will explain stabilization policies in more detail, but there are essentially two types of stabilization policy: fiscal policy and monetary policy. Fiscal policyThe use of government purchases, transfer payments, and taxes to influence the level of economic activity. is the use of government purchases, transfer payments, and taxes to influence the level of economic activity. Monetary policyThe use of central bank policies to influence the level of economic activity. is the use of central bank policies to influence the level of economic activity.

To Intervene or Not to Intervene: An Introduction to the Controversy

How large are inflationary and recessionary gaps? Panel (a) of Figure 7.16 "Real GDP and Potential Output" shows potential output versus the actual level of real GDP in the United States since 1960. Real GDP appears to follow potential output quite closely, although you see some periods where there have been inflationary or recessionary gaps. Panel (b) shows the sizes of these gaps expressed as percentages of potential output. The percentage gap is positive during periods of inflationary gaps and negative during periods of recessionary gaps. Over the last 50 years, the economy has seldom departed by more than 5% from its potential output. So the size and duration of the recessionary gap from 2009 to 2011 certainly stand out.

Figure 7.16 Real GDP and Potential Output

Panel (a) shows potential output (the blue line) and actual real GDP (the purple line) since 1960. Panel (b) shows the gap between potential and actual real GDP expressed as a percentage of potential output. Inflationary gaps are shown in green and recessionary gaps are shown in yellow.

Source: Bureau of Economic Analysis, NIPA Table 1.1.6 (revised February 29, 2012). Real Gross Domestic Product, Chained Dollars [Billions of chained (2005) dollars]. Seasonally adjusted at annual rates; Congressional Budget Office, The Budget and Economic Outlook: An Update, August 2011.

Panel (a) gives a long-run perspective on the economy. It suggests that the economy generally operates at about potential output. In Panel (a), the gaps seem minor. Panel (b) gives a short-run perspective; the view it gives emphasizes the gaps. Both of these perspectives are important. While it is reassuring to see that the economy is often close to potential, the years in which there are substantial gaps have real effects: Inflation or unemployment can harm people.

Some economists argue that stabilization policy can and should be used when recessionary or inflationary gaps exist. Others urge reliance on the economy’s own ability to correct itself. They sometimes argue that the tools available to the public sector to influence aggregate demand are not likely to shift the curve, or they argue that the tools would shift the curve in a way that could do more harm than good.

Economists who advocate stabilization policies argue that prices are sufficiently sticky that the economy’s own adjustment to its potential will be a slow process—and a painful one. For an economy with a recessionary gap, unacceptably high levels of unemployment will persist for too long a time. For an economy with an inflationary gap, the increased prices that occur as the short-run aggregate supply curve shifts upward impose too high an inflation rate in the short run. These economists believe it is far preferable to use stabilization policy to shift the aggregate demand curve in an effort to shorten the time the economy is subject to a gap.

Economists who favor a nonintervention approach accept the notion that stabilization policy can shift the aggregate demand curve. They argue, however, that such efforts are not nearly as simple in the real world as they may appear on paper. For example, policies to change real GDP may not affect the economy for months or even years. By the time the impact of the stabilization policy occurs, the state of the economy might have changed. Policy makers might choose an expansionary policy when a contractionary one is needed or vice versa. Other economists who favor nonintervention also question how sticky prices really are and if gaps even exist.

The debate over how policy makers should respond to recessionary and inflationary gaps is an ongoing one. These issues of nonintervention versus stabilization policies lie at the heart of the macroeconomic policy debate. We will return to them as we continue our analysis of the determination of output and the price level.

Key Takeaways

• When the aggregate demand and short-run aggregate supply curves intersect below potential output, the economy has a recessionary gap. When they intersect above potential output, the economy has an inflationary gap.
• Inflationary and recessionary gaps are closed as the real wage returns to equilibrium, where the quantity of labor demanded equals the quantity supplied. Because of nominal wage and price stickiness, however, such an adjustment takes time.
• When the economy has a gap, policy makers can choose to do nothing and let the economy return to potential output and the natural level of employment on its own. A policy to take no action to try to close a gap is a nonintervention policy.
• Alternatively, policy makers can choose to try to close a gap by using stabilization policy. Stabilization policy designed to increase real GDP is called expansionary policy. Stabilization policy designed to decrease real GDP is called contractionary policy.

Try It!

Using the scenario of the Great Depression of the 1930s, as analyzed in the previous Try It!, tell what kind of gap the U.S. economy faced in 1933, assuming the economy had been at potential output in 1929. Do you think the unemployment rate was above or below the natural rate of unemployment? How could the economy have been brought back to its potential output?

Case in Point: This Time Is Different, Or Is It?

In an analysis that spans 66 countries over nearly eight centuries, economists Carmen Reinhart and Kenneth Rogoff investigate hundreds of financial crises and the economic busts each leaves in its wake. With a database that includes crisis episodes that go back as far as 12th-century China and medieval Europe and continue until the financial crisis of 2007–2008, the authors look at the patterns of economic behavior that characterize the periods leading up to financial crises and the patterns that characterize the recoveries.

They argue that looking over a long period of history is necessary because financial crises are “rare” events. Financial crises occur at varying intervals, and researchers studying a period of 25 years or so may not encounter the equivalent of a 100-year, category 5 hurricane that hits a major, low-lying city with a faulty levee system.

In general, such crises follow periods of relative economic calm. For example, the period in the United States from the mid-1980s until 2007 was often referred to as the Great Moderation. During such periods, inflationary and recessionary gaps may occur, but they are relatively small and short-lived. Societies begin to feel that they have tamed the business cycle, that policy makers have gotten smarter, and that moderation will continue.

But then it happens. The accumulation of too much debt by governments, businesses, or consumers leads to a financial meltdown. As housing prices are run up, for example, people tend to find ways to justify their heavy borrowing and to rationalize the ascent in prices: Demographics have changed; mortgage terms have improved; the regulation we have put in place is better this time; it’s better to buy now, before prices go up even more; housing prices won’t fall. Memories of the last crisis fade. “This time is different,” they argue.

But Reinhart and Rogoff provide convincing evidence that “this time” is usually not different. Large-scale debt buildups lead to crises of confidence, and a financial crisis ensues. The aftermath is typically a severe and prolonged recessionary gap. On average, they find the following to be true:

1. The collapse in asset market prices is large and long-lasting. Housing prices decline an average of 35% over 6 years, and stock prices decline an average of 56% over 3.5 years.
2. Peak-to-trough GDP falls 9% on average, and the recession averages 2 years in length.
3. The unemployment rate rises 7 percentage points over a 4-year period.
4. Government debt swells due to bailout costs and, more importantly, because tax revenues fall off due to lower GDP.
5. V-shaped recoveries in stock prices are more common than V-shaped recoveries in housing prices or employment.

To what extent is the financial crisis of the late 2000s likely to follow this typical pattern? The authors argue that experience with expansionary fiscal policy in such circumstances is actually quite limited. Most often, governments are shut out of borrowing markets when crises hit. Japan’s government explicitly tried to implement fiscal stimulus, but the authors warn against drawing conclusions from one such example. The authors caution that governments should weigh any potential benefit of fiscal stimulus against the problem of higher public debt. They also note that central banks in 2007–2008 acted quickly and aggressively with expansionary monetary policies. But, they caution against “push[ing] too far the conceit that we are smarter than our predecessors” (p. 238). The global nature of the current situation only adds to the difficulty of recovering fully.

There was a company failure around 15 years ago that looked like a big deal at the time, but now seems like little more than a blip. The authors quote a trader who, during this event, presciently remarked, “More money has been lost because of four words than at the point of a gun. Those words are ‘This time is different.’”

Source: Carmen M. Reinhart and Kenneth S. Rogoff, This Time Is Different: Eight Centuries of Financial Folly (Princeton: Princeton University Press, 2009).

Answer to Try It! Problem

To the graph in the previous Try It! problem we add the long-run aggregate supply curve to show that, with output below potential, the U.S. economy in 1933 was in a recessionary gap. The unemployment rate was above the natural rate of unemployment. Indeed, real GDP in 1933 was about 30% below what it had been in 1929, and the unemployment rate had increased from 3% to 25%. Note that during the period of the Great Depression, wages did fall. The notion of nominal wage and other price stickiness discussed in this section should not be construed to mean complete wage and price inflexibility. Rather, during this period, nominal wages and other prices were not flexible enough to restore the economy to the potential level of output. There are two basic choices on how to close recessionary gaps. Nonintervention would mean waiting for wages to fall further. As wages fall, the short-run aggregate supply curve would continue to shift to the right. The alternative would be to use some type of expansionary policy. This would shift the aggregate demand curve to the right. These two options were illustrated in Figure 7.15 "Alternatives in Closing an Inflationary Gap".

Defining Economic Growth

Economic growth is a long-run process that occurs as an economy’s potential output increases. Changes in real GDP from quarter to quarter or even from year to year are short-run fluctuations that occur as aggregate demand and short-run aggregate supply change. Regardless of media reports stating that the economy grew at a certain rate in the last quarter or that it is expected to grow at a particular rate during the next year, short-run changes in real GDP say little about economic growth. In the long run, economic activity moves toward its level of potential output. Increases in potential constitute economic growth.

Earlier we defined economic growth as the process through which an economy achieves an outward shift in its production possibilities curve. How does a shift in the production possibilities curve relate to a change in potential output? To produce its potential level of output, an economy must operate on its production possibilities curve. An increase in potential output thus implies an outward shift in the production possibilities curve. In the framework of the macroeconomic model of aggregate demand and aggregate supply, we show economic growth as a shift to the right in the long-run aggregate supply curve.

There are three key points about economic growth to keep in mind:

1. Growth is a process. It is not a single event; rather, it is an unfolding series of events.
2. We define growth in terms of the economy’s ability to produce goods and services, as indicated by its level of potential output.
3. Growth suggests that the economy’s ability to produce goods and services is rising. A discussion of economic growth is thus a discussion of the series of events that increase the economy’s ability to produce goods and services.

Figure 8.1 "A Century of Economic Growth" shows the record of economic growth for the U.S. economy over the past century. The graph shows annual levels of actual real GDP and of potential output. We see that the economy has experienced dramatic growth over the past century; potential output has soared nearly 20-fold. The figure also reminds us of a central theme of our analysis of macroeconomics: real GDP fluctuates about potential output. Real GDP sagged well below its potential (initially more than 40% below and then remaining at about 20% below for most of the decade) during the Great Depression of the 1930s and rose well above its potential (about 30% above) as the nation mobilized its resources to fight World War II. With the exception of these two periods, real GDP has remained fairly close to the economy’s potential output. In the recession of 1981, real GDP was about 6.5% below its potential, and during the recession that began at the end of 2007, real GDP fell nearly 8% below its potential. In 2011, the economy was still about 6.8% below its potential. Nonetheless, since 1950, the actual level of real GDP has deviated from potential output by an average of less than 2%.

Figure 8.1 A Century of Economic Growth

At the start of the 21^st century, the level of potential output reached a level nearly 20 times its level a century earlier. Over the years, actual real GDP fluctuated about a rising level of potential output.

Sources: 1910–1949 data from Christina D. Romer, “World War I and the Postwar Depression: A Reinterpretation Based on Alternative Estimates of GNP,” Journal of Monetary Economics 22 (1988): 91–115; data for 1950–2010 from Congressional Budget Office, The Budget and Economic Outlook: An Update, August 2011 and from Bureau of Economic Analysis, NIPA Table 1.1.6.

We urge you to take some time with Figure 8.1 "A Century of Economic Growth". Over the course of the last century, it is economic growth that has taken center stage. Certainly, the fluctuations about potential output have been important. The recessionary gaps—periods when real GDP slipped below its potential—were often wrenching experiences in which millions of people endured great hardship. The inflationary gaps—periods when real GDP rose above its potential level—often produced dramatic increases in price levels. Those fluctuations mattered. It was the unemployment and/or the inflation that came with them that made headlines. But it was the quiet process of economic growth that pushed living standards ever higher. We must understand growth if we are to understand how we got where we are, and where we are likely to be going during the 21st century.

Figure 8.2 "Cyclical Change Versus Growth" tells us why we use changes in potential output, rather than actual real GDP, as our measure of economic growth. Actual values of real GDP are affected not just by changes in the potential level of output, but also by the cyclical fluctuations about that level of output.

Given our definition of economic growth, we would say that the hypothetical economy depicted in Figure 8.2 "Cyclical Change Versus Growth" grew at a 2.5% annual rate throughout the period. If we used actual values of real GDP, however, we would obtain quite different interpretations. Consider, for example, the first decade of this period: it began with a real GDP of $900 billion and a recessionary gap, and it ended in year 10 with a real GDP of $1,408 billion and an inflationary gap. If we record growth as the annual rate of change between these levels, we find an annual rate of growth of 4.6%—a rather impressive performance.

Figure 8.2 Cyclical Change Versus Growth

The use of actual values of real GDP to measure growth can give misleading results. Here, an economy’s potential output (shown in green) grows at a steady rate of 2.5% per year, with actual values of real GDP fluctuating about that trend. If we measure growth in the first 10 years as the annual rate of change between beginning and ending values of real GDP, we get a growth rate of 4.6%. The rate for the second decade is 0.5%. Growth estimates based on changes in real GDP are affected by cyclical changes that do not represent economic growth.

Now consider the second decade shown in Figure 8.2 "Cyclical Change Versus Growth". It began in year 10, and it ended in year 20 with a recessionary gap. If we measure the growth rate over that period by looking at beginning and ending values of actual real GDP, we compute an annual growth rate of 0.5%. Viewed in this way, performance in the first decade is spectacular while performance in the second is rather lackluster. But these figures depend on the starting and ending points we select; the growth rate of potential output was 2.5% throughout the period.

By measuring economic growth as the rate of increase in potential output, we avoid such problems. One way to do this is to select years in which the economy was operating at the natural level of employment and then to compute the annual rate of change between those years. The result is an estimate of the rate at which potential output increased over the period in question. For the economy shown in Figure 8.2 "Cyclical Change Versus Growth", for example, we see that real GDP equaled its potential in years 5 and 15. Real GDP in year 5 was $1,131, and real GDP in year 15 was $1,448. The annual rate of change between these two years was 2.5%. If we have estimates of potential output, of course, we can simply compute annual rates of change between any two years.

The Rule of 72 and Differences in Growth Rates

The Case in Point on presidents and growth at the end of this section suggests a startling fact: the U.S. growth rate began slowing in the 1970s, did not recover until the mid-1990s, only to slow down again in the 2000s. The question we address here is: does it matter? Does a percentage point drop in the growth rate make much difference? It does. To see why, let us investigate what happens when a variable grows at a particular percentage rate.

Suppose two economies with equal populations start out at the same level of real GDP but grow at different rates. Economy A grows at a rate of 3.5%, and Economy B grows at a rate of 2.4%. After a year, the difference in real GDP will hardly be noticeable. After a decade, however, real GDP in Economy A will be 11% greater than in Economy B. Over longer periods, the difference will be more dramatic. After 100 years, for example, income in Economy A will be nearly three times as great as in Economy B. If population growth in the two countries has been the same, the people of Economy A will have a far higher standard of living than those in Economy B. The difference in real GDP per person will be roughly equivalent to the difference that exists today between Great Britain and Mexico.

Over time, small differences in growth rates create large differences in incomes. An economy growing at a 3.5% rate increases by 3.5% of its initial value in the first year. In the second year, the economy increases by 3.5% of that new, higher value. In the third year, it increases by 3.5% of a still higher value. When a quantity grows at a given percentage rate, it experiences exponential growthWhen a quantity grows at a given percentage rate.. A variable that grows exponentially follows a path such as those shown for potential output in Figure 8.1 "A Century of Economic Growth" and Figure 8.2 "Cyclical Change Versus Growth". These curves become steeper over time because the growth rate is applied to an ever-larger base.

A variable growing at some exponential rate doubles over fixed intervals of time. The doubling time is given by the rule of 72A variable’s approximate doubling time equals 72 divided by the growth rate, stated as a whole number., which states that a variable’s approximate doubling time equals 72 divided by the growth rate, stated as a whole number. If the level of income were increasing at a 9% rate, for example, its doubling time would be roughly 72/9, or 8 years.Notice the use of the words roughly and approximately. The actual value of an income of $1,000 growing at rate r for a period of n years is $1,000 × (1 + r)ⁿ. After 8 years of growth at a 9% rate, income would thus be $1,000 (1 + 0.09)⁸ = $1,992.56. The rule of 72 predicts that its value will be $2,000. The rule of 72 gives an approximation, not an exact measure, of the impact of exponential growth.

Let us apply this concept of a doubling time to the reduction in the U.S. growth rate. Had the U.S. economy continued to grow at a 3.5% rate after 1970, then its potential output would have doubled roughly every 20 years (72/3.5 = 20). That means potential output would have doubled by 1990, would double again by 2010, and would double again by 2030. Real GDP in 2030 would thus be eight times as great as its 1970 level. Growing at a 2.4% rate, however, potential output doubles only every 30 years (72/2.4 = 30). It would take until 2000 to double once from its 1970 level, and it would double once more by 2030. Potential output in 2030 would thus be four times its 1970 level if the economy grew at a 2.4% rate (versus eight times its 1970 level if it grew at a 3.5% rate). The 1.1% difference in growth rates produces a 100% difference in potential output by 2030. The different growth paths implied by these growth rates are illustrated in Figure 8.3 "Differences in Growth Rates".

Figure 8.3 Differences in Growth Rates

The chart suggests the significance in the long run of a small difference in the growth rate of real GDP. We begin in 1970, when real GDP equaled $2,873.9 billion. If real GDP grew at an annual rate of 3.5% from that year, it would double roughly every 20 years: in 1990, 2010, and 2030. Growth at a 2.4% rate, however, implies doubling every 30 years: in 2000 and 2030. By 2030, the 3.5% growth rate leaves real GDP at twice the level that would be achieved by 2.4% growth.

Growth in Output per Capita

Of course, it is not just how fast potential output grows that determines how fast the average person’s material standard of living rises. For that purpose, we examine economic growth on a per capita basis. An economy’s output per capitaReal GDP per person. equals real GDP per person. If we let N equal population, then

In the United States in the third quarter of 2010, for example, real GDP was $13,277.4 billion (annual rate). The U.S. population was 311.0 million. Real U.S. output per capita thus equaled $42,693.

We use output per capita as a gauge of an economy’s material standard of living. If the economy’s population is growing, then output must rise as rapidly as the population if output per capita is to remain unchanged. If, for example, population increases by 2%, then real GDP would have to rise by 2% to maintain the current level of output per capita. If real GDP rises by less than 2%, output per capita will fall. If real GDP rises by more than 2%, output per capita will rise. More generally, we can write:

For economic growth to translate into a higher standard of living on average, economic growth must exceed population growth. From 1970 to 2004, for example, Sierra Leone’s population grew at an annual rate of 2.1% per year, while its real GDP grew at an annual rate of 1.4%; its output per capita thus fell at a rate of 0.7% per year. Over the same period, Singapore’s population grew at an annual rate of 2.1% per year, while its real GDP grew 7.4% per year. The resultant 5.3% annual growth in output per capita transformed Singapore from a relatively poor country to a country with the one of the highest per capita incomes in the world.

Case in Point: Presidents and Economic Growth

President	Annual Increase in Real GDP (%)	Growth Rate (%)
Truman 1949–1952	5.4	4.4
Eisenhower 1953–1960	2.5	3.3
Kennedy-Johnson 1961–1968	5.1	4.4
Nixon-Ford 1969–1976	2.8	3.4
Carter 1977–1980	3.2	3.1
Reagan 1981–1988	3.5	3.1
G. H. W. Bush 1989–1992	2.1	2.9
Clinton 1993–2000	3.8	3.3
G. W. Bush 2001–2008	1.6	2.6

Presidents are often judged by the rate at which the economy grew while they were in office. This test is unfair on two counts. First, a president has little to do with the forces that determine growth. And second, such tests simply compute the annual rate of growth in real GDP over the course of a presidential term, which we know can be affected by cyclical factors. A president who takes office when the economy is down and goes out with the economy up will look like an economic star; a president with the bad luck to have reverse circumstances will seem like a dud. Here are annual rates of change in real GDP for each of the postwar presidents, together with rates of economic growth, measured as the annual rate of change in potential output.

The presidents’ economic records are clearly affected by luck. Presidents Truman, Kennedy, Reagan, and Clinton, for example, began their terms when the economy had a recessionary gap and ended them with an inflationary gap or at about potential output. Real GDP thus rose faster than potential output during their presidencies. The Eisenhower, Nixon-Ford, G. H. W. Bush, and G. W. Bush administrations each started with an inflationary gap or at about potential and ended with a recessionary gap, thus recording rates of real GDP increase below the rate of gain in potential. Only Jimmy Carter, who came to office and left it with recessionary gaps, presided over a relatively equivalent rate of increase in actual GDP versus potential output.

How did Barack Obama fare? As this case was written after he was in office for less than a full term, you will have to check for yourself!

The Aggregate Production Function

An aggregate production functionFunction that relates the total output of an economy to the total amount of labor employed in the economy, all other determinants of production (capital, natural resources, and technology) being unchanged. relates the total output of an economy to the total amount of labor employed in the economy, all other determinants of production (that is, capital, natural resources, and technology) being unchanged. An economy operating on its aggregate production function is producing its potential level of output.

Figure 8.5 "The Aggregate Production Function" shows an aggregate production function (PF). It shows output levels for a range of employment between 120 million and 140 million workers. When the level of employment is 120 million, the economy produces a real GDP of $11,500 billion (point A). A level of employment of 130 million produces a real GDP of $12,000 billion (point B), and when 140 million workers are employed, a real GDP of $12,300 billion is produced (point C). In drawing the aggregate production function, the amount of labor varies, but everything else that could affect output, specifically the quantities of other factors of production and technology, is fixed.

The shape of the aggregate production function shows that as employment increases, output increases, but at a decreasing rate. Increasing employment from 120 million to 130 million, for example, increases output by $500 billion to $12,000 billion at point B. The next 10 million workers increase production by $300 billion to $12,300 billion at point C. This example illustrates diminishing marginal returns. Diminishing marginal returnsSituation that occurs when additional units of a variable factor add less and less to total output, given constant quantities of other factors. occur when additional units of a variable factor add less and less to total output, given constant quantities of other factors.

Figure 8.5 The Aggregate Production Function

An aggregate production function (PF) relates total output to total employment, assuming all other factors of production and technology are fixed. It shows that increases in employment lead to increases in output but at a decreasing rate.

It is easy to picture the problem of diminishing marginal returns in the context of a single firm. The firm is able to increase output by adding workers. But because the firm’s plant size and stock of equipment are fixed, the firm’s capital per worker falls as it takes on more workers. Each additional worker adds less to output than the worker before. The firm, like the economy, experiences diminishing marginal returns.

The Aggregate Production Function, the Market for Labor, and Long-Run Aggregate Supply

To derive the long-run aggregate supply curve, we bring together the model of the labor market, introduced in the first macro chapter and the aggregate production function.

As we learned, the labor market is in equilibrium at the natural level of employment. The demand and supply curves for labor intersect at the real wage at which the economy achieves its natural level of employment. We see in Panel (a) of Figure 8.6 "Deriving the Long-Run Aggregate Supply Curve" that the equilibrium real wage is ω₁ and the natural level of employment is L₁. Panel (b) shows that with employment of L₁, the economy can produce a real GDP of Y_P. That output equals the economy’s potential output. It is that level of potential output that determines the position of the long-run aggregate supply curve in Panel (c).

Figure 8.6 Deriving the Long-Run Aggregate Supply Curve

Panel (a) shows that the equilibrium real wage is ω₁, and the natural level of employment is L₁. Panel (b) shows that with employment of L₁, the economy can produce a real GDP of Y_P. That output equals the economy’s potential output. It is at that level of potential output that we draw the long-run aggregate supply curve in Panel (c).

Changes in Long-Run Aggregate Supply

The position of the long-run aggregate supply curve is determined by the aggregate production function and the demand and supply curves for labor. A change in any of these will shift the long-run aggregate supply curve.

Figure 8.7 "Shift in the Aggregate Production Function and the Long-Run Aggregate Supply Curve" shows one possible shifter of long-run aggregate supply: a change in the production function. Suppose, for example, that an improvement in technology shifts the aggregate production function in Panel (b) from PF₁ to PF₂. Other developments that could produce an upward shift in the curve include an increase in the capital stock or in the availability of natural resources.

Figure 8.7 Shift in the Aggregate Production Function and the Long-Run Aggregate Supply Curve

An improvement in technology shifts the aggregate production function upward in Panel (b). Because labor is more productive, the demand for labor shifts to the right in Panel (a), and the natural level of employment increases to L₂. In Panel (c) the long-run aggregate supply curve shifts to the right to Y₂.

The shift in the production function to PF₂ means that labor is now more productive than before. This will affect the demand for labor in Panel (a). Before the technological change, firms employed L₁ workers at a real wage ω₁. If workers are more productive, firms will find it profitable to hire more of them at ω₁. The demand curve for labor thus shifts to D₂ in Panel (a). The real wage rises to ω₂, and the natural level of employment rises to L₂. The increase in the real wage reflects labor’s enhanced productivityThe amount of output per worker., the amount of output per worker. To see how potential output changes, we see in Panel (b) how much output can be produced given the new natural level of employment and the new aggregate production function. The real GDP that the economy is capable of producing rises from Y₁ to Y₂. The higher output is a reflection of a higher natural level of employment, along with the fact that labor has become more productive as a result of the technological advance. In Panel (c) the long-run aggregate supply curve shifts to the right to the vertical line at Y₂.

This analysis dispels a common misconception about the impact of improvements in technology or increases in the capital stock on employment. Some people believe that technological gains or increases in the stock of capital reduce the demand for labor, reduce employment, and reduce real wages. Certainly the experience of the United States and most other countries belies that notion. Between 1990 and 2007, for example, the U.S. capital stock and the level of technology increased dramatically. During the same period, employment and real wages rose, suggesting that the demand for labor increased by more than the supply of labor. As some firms add capital or incorporate new technologies, some workers at those firms may lose their jobs. But for the economy as a whole, new jobs become available and they generally offer higher wages. The demand for labor rises.

Another event that can shift the long-run aggregate supply curve is an increase in the supply of labor, as shown in Figure 8.8 "Increase in the Supply of Labor and the Long-Run Aggregate Supply Curve". An increased supply of labor could result from immigration, an increase in the population, or increased participation in the labor force by the adult population. Increased participation by women in the labor force, for example, has tended to increase the supply curve for labor during the past several decades.

Figure 8.8 Increase in the Supply of Labor and the Long-Run Aggregate Supply Curve

An increase in the supply of labor shifts the supply curve in Panel (a) to S₂, and the natural level of employment rises to L₂. The real wage falls to ω₂. With increased labor, the aggregate production function in Panel (b) shows that the economy is now capable of producing real GDP at Y₂. The long-run aggregate supply curve in Panel (c) shifts to LRAS₂.

In Panel (a), an increase in the labor supply shifts the supply curve to S₂. The increase in the supply of labor does not change the stock of capital or natural resources, nor does it change technology—it therefore does not shift the aggregate production function. Because there is no change in the production function, there is no shift in the demand for labor. The real wage falls from ω₁ to ω₂ in Panel (a), and the natural level of employment rises from L₁ to L₂. To see the impact on potential output, Panel (b) shows that employment of L₂ can produce real GDP of Y₂. The long-run aggregate supply curve in Panel (c) thus shifts to LRAS₂. Notice, however, that this shift in the long-run aggregate supply curve to the right is associated with a reduction in the real wage to ω₂.

Of course, the aggregate production function and the supply curve of labor can shift together, producing higher real wages at the same time population rises. That has been the experience of most industrialized nations. The increase in real wages in the United States between 1990 and 2007, for example, came during a period in which an increasing population increased the supply of labor. The demand for labor increased by more than the supply, pushing the real wage up. The accompanying Case in Point looks at gains in real wages in the face of technological change, an increase in the stock of capital, and rapid population growth in the United States during the 19th century.

Our model of long-run aggregate supply tells us that in the long run, real GDP, the natural level of employment, and the real wage are determined by the economy’s production function and by the demand and supply curves for labor. Unless an event shifts the aggregate production function, the demand curve for labor, or the supply curve for labor, it affects neither the natural level of employment nor potential output. Economic growth occurs only if an event shifts the economy’s production function or if there is an increase in the demand for or the supply of labor.

Key Takeaways

• The aggregate production function relates the level of employment to the level of real GDP produced per period.
• The real wage and the natural level of employment are determined by the intersection of the demand and supply curves for labor. Potential output is given by the point on the aggregate production function corresponding to the natural level of employment. This output level is the same as that shown by the long-run aggregate supply curve.
• Economic growth can be shown as a series of shifts to the right in LRAS. Such shifts require either upward shifts in the production function or increases in demand for or supply of labor.

Try It!

Suppose that the quantity of labor supplied is 50 million workers when the real wage is $20,000 per year and that potential output is $2,000 billion per year. Draw a three-panel graph similar to the one presented in Figure 8.8 "Increase in the Supply of Labor and the Long-Run Aggregate Supply Curve" to show the economy’s long-run equilibrium. Panel (a) of your graph should show the demand and supply curves for labor, Panel (b) should show the aggregate production function, and Panel (c) should show the long-run aggregate supply curve. Now suppose a technological change increases the economy’s output with the same quantity of labor as before to $2,200 billion, and the real wage rises to $21,500. In response, the quantity of labor supplied increases to 51 million workers. In the same three panels you have already drawn, sketch the new curves that result from this change. Explain what happens to the level of employment, the level of potential output, and the long-run aggregate supply curve. (Hint: you have information for only one point on each of the curves you draw—two for the supply of labor; simply draw curves of the appropriate shape. Do not worry about getting the scale correct.)

Case in Point: Technological Change, Employment, and Real Wages During the Industrial Revolution

Technological change and the capital investment that typically comes with it are often criticized because they replace labor with machines, reducing employment. Such changes, critics argue, hurt workers. Using the model of aggregate demand and aggregate supply, however, we arrive at a quite different conclusion. The model predicts that improved technology will increase the demand for labor and boost real wages.

The period of industrialization, generally taken to be the time between the Civil War and World War I, was a good test of these competing ideas. Technological changes were dramatic as firms shifted toward mass production and automation. Capital investment soared. Immigration increased the supply of labor. What happened to workers?

Employment more than doubled during this period, consistent with the prediction of our model. It is harder to predict, from a theoretical point of view, the consequences for real wages. The latter third of the 19th century was a period of massive immigration to the United States. Between 1865 and 1880, more than 5 million people came to the United States from abroad; most were of working age. The pace accelerated between 1880 and 1923, when more than 23 million people moved to the United States from other countries. Immigration increased the supply of labor, which should reduce the real wage. There were thus two competing forces at work: Technological change and capital investment tended to increase real wages, while immigration tended to reduce them by increasing the supply of labor.

The evidence suggests that the forces of technological change and capital investment proved far more powerful than increases in labor supply. Real wages soared 60% between 1860 and 1890. They continued to increase after that. Real wages in manufacturing, for example, rose 37% from 1890 to 1914.

Technological change and capital investment displace workers in some industries. But for the economy as a whole, they increase worker productivity, increase the demand for labor, and increase real wages.

Sources: Wage data taken from Clarence D. Long, Wages and Earnings in the United States, 1860–1990 (Princeton, NJ: Princeton University Press, 1960), p. 109, and from Albert Rees, Wages in Manufacturing, 1890–1914 (Princeton, NJ: Princeton University Press, 1961), pp. 3–5. Immigration figures taken from Gary M. Walton and Hugh Rockoff, History of the American Economy, 6th ed. (New York: Harcourt Brace Jovanovich, 1990), p. 371.

Answer to Try It! Problem

The production function in Panel (b) shifts up to PF₂. Because it reflects greater productivity of labor, firms will increase their demand for labor, and the demand curve for labor shifts to D₂ in Panel (a). LRAS₁ shifts to LRAS₂ in Panel (c). Employment and potential output rise. Potential output will be greater than $2,200 billion.

The Sources of Economic Growth

As we have learned, there are two ways to model economic growth: (1) as an outward shift in an economy’s production possibilities curve, and (2) as a shift to the right in its long-run aggregate supply curve. In drawing either one at a point in time, we assume that the economy’s factors of production and its technology are unchanged. Changing these will shift both curves. Therefore, anything that increases the quantity or quality of factors of production or that improves the technology available to the economy contributes to economic growth.

The sources of growth for the U.S. economy in the 20th century were presented in the chapter on choices in production. There we learned that the main sources of growth for the United States from 1960 to 2007 were divided between increases in the quantities of labor and of physical capital (about 65%) and in improvements in the qualities of the factors of production and technology (about 35%). Since 2000, however, the contributions from improvements in factor quality and technology have accounted for about half the economic growth in the United States.

In order to devote resources to increasing physical and human capital and to improving technology—activities that will enhance future production—society must forgo using them now to produce consumer goods. Even though the people in the economy would enjoy a higher standard of living today without this sacrifice, they are willing to reduce present consumption in order to have more goods and services available for the future.

As a college student, you personally made such a choice. You decided to devote time to study that you could have spent earning income. With the higher income, you could enjoy greater consumption today. You made this choice because you expect to earn higher income in the future and thus to enjoy greater consumption in the future. Because many other people in the society also choose to acquire more education, society allocates resources to produce education. The education produced today will enhance the society’s human capital and thus its economic growth.

All other things equal, higher saving allows more resources to be devoted to increases in physical and human capital and technological improvement. In other words, saving, which is income not spent on consumption, promotes economic growth by making available resources that can be channeled into growth-enhancing uses.

Explaining Recent Disparities in Growth Rates

Toward the end of the 20th century, it appeared that some of the world’s more affluent countries were growing robustly while others were growing more slowly or even stagnating. This observation was confirmed in a major study by the Organisation for Economic Co-operation and Development (OECD),The material in this section is based on Organisation for Economic Co-operation and Development, The Sources of Economic Growth in OECD Countries, 2003. whose members are listed in Table 8.1 "Growing Disparities in Rates of Economic Growth". The table shows that for the OECD countries as a whole, economic growth per capita fell from an average of 2.2% per year in the 1980s to an average of 1.9% per year in the 1990s. The higher standard deviation in the latter period confirms an increased disparity of growth rates in the more recent period. Moreover, the data on individual countries show that per capita growth in some countries (specifically, the United States, Canada, Ireland, Netherlands, Norway, and Spain) picked up, especially in the latter half of the 1990s, while it decelerated in most of the countries of continental Europe and Japan.

The study goes on to try to explain the reasons for the divergent growth trends. The main findings were:

• In general, countries with accelerating per capita growth rates also experienced significant increases in employment, while those with stagnant or declining employment generally experienced reductions in per capita growth rates.
• Enhancements in human capital contributed to labor productivity and economic growth, but in slower growing countries such improvements were not enough to offset the impact of reduced or stagnant labor utilization.
• Information and communication technology has contributed to economic growth both through rapid technological progress within the information and communication technology industry itself as well as, more recently, through the use of information and communication technology equipment in other industries. This has made an important contribution to growth in several of the faster growing countries.
• Other factors associated with more growth include: investments in physical and human capital, sound macroeconomic policies (especially low inflation), private sector research and development, trade exposure, and better developed financial markets. Results concerning the impact of the size of the government and of public sector research and development on growth were more difficult to interpret.
• With qualifications, the study found that strict regulation of product markets (for example, regulations that reduce competition) and strict employment protection legislation (for example, laws that make hiring and firing of workers more difficult) had negative effects on growth.
• All countries show a large number of firms entering and exiting markets. But, a key difference between the United States and Europe is that new firms in the United States start out smaller and less productive than those of Europe but grow faster when they are successful. The report hypothesizes that lower start-up costs and less strict labor market regulations may encourage U.S. entrepreneurs to enter a market and then to expand, if warranted. European entrepreneurs may be less willing to experiment in a market in the first place.

The general concern in the second half of the 1970s and the 1980s was that economic growth was slowing down and that it might not be possible to reverse this pattern. The 1990s and early 2000s, in which growth picked up in some countries but not in others, suggested that the problem was not universal and led to a search for the reasons for the disparities in growth rates that emerged. The OECD study described above gives some possible explanations. The findings of that study practically beg countries to examine closely their economic policies at a variety of levels and to consider changes that may add flexibility to their economies.

To spur this process, in 2005, the OECD started a new annual publication called Going for Growth. The inaugural edition identified five priority structural policy areas specific to each OECD country. The policies were categorized as either improving labor utilization or improving productivity. Suggestions for improved labor utilization ranged from changing tax policies to improving incentives for females to enter, and for older people to remain in, the workforce. Suggestions for improved productivity ranged from education reform to privatization of state-owned industries. As an example, the priorities proposed for the United States in 2005 included (1) limiting increases in labor costs by reforming Medicare to restrain health care costs, (2) encouraging private saving by shifting the burden of taxation toward consumption, (3) improving primary and secondary education, (4) reducing trade-distorting agricultural price supports, and (5) promoting transparency and accountability of corporate governance.Organisation for Economic Co-operation and Development, Economic Policy Reforms: Going for Growth 2005, available at http://www.OECD.org/economics/goingforgrowth.

The 2010 edition of Going for GrowthOrganisation for Economic Co-operation and Development, Economic Policy Reforms: Going for Growth 2010, available at http://www.OECD.org/economics/goingforgrowth. took stock of the progress made over the five-year period leading up to 2010. While two-thirds of the OECD countries took some legislative action in at least one priority area, the scope and depth of this progress varied immensely across countries.

Figure 8.9 " of " summarizes this progress using two alternative measures. Panel (a) shows a responsiveness rate, which measures significant actions taken, and Panel (b) shows a follow-through rate, which measures whether priorities could be dropped due to reform implementation.

As we can see, the responsiveness and follow-through rates vary widely. Turkey and the Czech Republic stand out as the countries having undertaken substantial reform. The United States stands out as the country having shown neither responsiveness nor follow-through. While the relatively strong performance of the United States at the end of the 20th century, as shown in Table 8.1 "Growing Disparities in Rates of Economic Growth", could indicate relatively less need for growth-enhancing reforms, the comparative lack of progress since 2005 raises doubt concerning the ability to maintain strong economic growth going forward.

Figure 8.9 of Going for Growth Recommendations across Countries since 2005

Panel (a) measures the 2005 to 2009 rate of responsiveness to the reform priorities given to each country in 2005. Panel (b) shows the reform follow-through rates. Growth-enhancing policy reforms across countries varied widely during this period.

Source: Organisation for Economic Co-operation and Development, Going for Growth 2010, Figure 2.6, p. 75.

In closing, it is worth reiterating that economic freedom and higher incomes tend to go together. Countries could not have attained high levels of income if they had not maintained the economic freedom that contributed to high incomes in the first place. Thus, it is also likely that rates of economic growth in the future will be related to the amount of economic freedom countries choose. We shall see in later chapters that monetary and fiscal policies that are used to stabilize the economy in the short run can also have an impact on long-run economic growth.

Case in Point: Economic Growth in Poor Countries … or Lack Thereof

Economist William Easterly in his aptly named book The Elusive Quest for Growth: Economists’ Adventures and Misadventures in the Tropics admits that after 50 years of searching for the magic formula for turning poor countries into rich ones, the quest remains elusive.

Poor countries just need more physical capital, you say? Easterly points out that between 1960 and 1985, the capital stock per worker in both Gambia and Japan rose by over 500%. The result? In Gambia, output per worker over the 25-year period rose 2%; in Japan, output per worker rose 260%.

So, it must be that poor countries need more human capital? Again, he finds startling comparisons. For example, human capital expanded faster in Zambia than in Korea, but Zambia’s annual growth rate is 7 percentage points below Korea’s.

Too much population growth? Too little? More foreign aid? Too much? As Easterly proceeds, writing a prescription for growth seems ever more difficult: “None has delivered as promised,” he concludes (p. xi).

While Easterly does not offer his own new panacea for how to move countries to a higher level of per capita GDP, where the model presented in this chapter does seem to provide some explanations of why a country’s growth rate may vary over time or differ from another country’s, he does argue that creating incentives for growth in poor countries is crucial. Acknowledging a role for plain luck, Easterly argues that good government policies—ones that keep low such negatives as inflation, corruption, and red tape—and quality institutions and laws—ones that, for example, honor contracts and reward merit—will help.

How to actually improve such incentives might constitute the next great quest:

“We have learned once and for all that there are no magical elixirs to bring a happy ending to our quest for growth. Prosperity happens when all the players in the development game have the right incentives. It happens when government incentives induce technological adaptation, high-quality investment in machines, and high-quality schooling. It happens when donors face incentives that induce them to give aid to countries with good policies where aid will have high payoffs, not to countries with poor policies where aid is wasted. It happens when the poor get good opportunities and incentives, which requires government welfare programs that reward rather than penalize earning income. It happens when politics is not polarized between antagonistic interest groups. . . . The solutions are a lot more difficult to describe than the problems. The way forward must be to create incentives for growth for the trinity of governments, donors, and individuals.” (p. 289–90)

Source: William Easterly, The Elusive Quest for Growth: Economists’ Adventures and Misadventures in the Tropics (Cambridge: MIT Press, 2002).

The Functions of Money

Money serves three basic functions. By definition, it is a medium of exchange. It also serves as a unit of account and as a store of value—as the “mack” did in Lompoc.

Types of Money

Although money can take an extraordinary variety of forms, there are really only two types of money: money that has intrinsic value and money that does not have intrinsic value.

Commodity moneyMoney that has value apart from its use as money. is money that has value apart from its use as money. Mackerel in federal prisons is an example of commodity money. Mackerel could be used to buy services from other prisoners; they could also be eaten.

Gold and silver are the most widely used forms of commodity money. Gold and silver can be used as jewelry and for some industrial and medicinal purposes, so they have value apart from their use as money. The first known use of gold and silver coins was in the Greek city-state of Lydia in the beginning of the seventh century B.C. The coins were fashioned from electrum, a natural mixture of gold and silver.

One disadvantage of commodity money is that its quantity can fluctuate erratically. Gold, for example, was one form of money in the United States in the 19th century. Gold discoveries in California and later in Alaska sent the quantity of money soaring. Some of this nation’s worst bouts of inflation were set off by increases in the quantity of gold in circulation during the 19th century. A much greater problem exists with commodity money that can be produced. In the southern part of colonial America, for example, tobacco served as money. There was a continuing problem of farmers increasing the quantity of money by growing more tobacco. The problem was sufficiently serious that vigilante squads were organized. They roamed the countryside burning tobacco fields in an effort to keep the quantity of tobacco, hence money, under control. (Remarkably, these squads sought to control the money supply by burning tobacco grown by other farmers.)

Another problem is that commodity money may vary in quality. Given that variability, there is a tendency for lower-quality commodities to drive higher-quality commodities out of circulation. Horses, for example, served as money in colonial New England. It was common for loan obligations to be stated in terms of a quantity of horses to be paid back. Given such obligations, there was a tendency to use lower-quality horses to pay back debts; higher-quality horses were kept out of circulation for other uses. Laws were passed forbidding the use of lame horses in the payment of debts. This is an example of Gresham’s law: the tendency for a lower-quality commodity (bad money) to drive a higher-quality commodity (good money) out of circulation. Unless a means can be found to control the quality of commodity money, the tendency for that quality to decline can threaten its acceptability as a medium of exchange.

But something need not have intrinsic value to serve as money. Fiat moneyMoney that some authority, generally a government, has ordered to be accepted as a medium of exchange. is money that some authority, generally a government, has ordered to be accepted as a medium of exchange. The currencyPaper money and coins.—paper money and coins—used in the United States today is fiat money; it has no value other than its use as money. You will notice that statement printed on each bill: “This note is legal tender for all debts, public and private.”

Checkable depositsBalances in checking accounts., which are balances in checking accounts, and traveler’s checks are other forms of money that have no intrinsic value. They can be converted to currency, but generally they are not; they simply serve as a medium of exchange. If you want to buy something, you can often pay with a check or a debit card. A checkA written order to a bank to transfer ownership of a checkable deposit. is a written order to a bank to transfer ownership of a checkable deposit. A debit card is the electronic equivalent of a check. Suppose, for example, that you have $100 in your checking account and you write a check to your campus bookstore for $30 or instruct the clerk to swipe your debit card and “charge” it $30. In either case, $30 will be transferred from your checking account to the bookstore’s checking account. Notice that it is the checkable deposit, not the check or debit card, that is money. The check or debit card just tells a bank to transfer money, in this case checkable deposits, from one account to another.

What makes something money is really found in its acceptability, not in whether or not it has intrinsic value or whether or not a government has declared it as such. For example, fiat money tends to be accepted so long as too much of it is not printed too quickly. When that happens, as it did in Russia in the 1990s, people tend to look for other items to serve as money. In the case of Russia, the U.S. dollar became a popular form of money, even though the Russian government still declared the ruble to be its fiat money.

Measuring Money

The total quantity of money in the economy at any one time is called the money supplyThe total quantity of money in the economy at any one time.. Economists measure the money supply because it affects economic activity. What should be included in the money supply? We want to include as part of the money supply those things that serve as media of exchange. However, the items that provide this function have varied over time.

Before 1980, the basic money supply was measured as the sum of currency in circulation, traveler’s checks, and checkable deposits. Currency serves the medium-of-exchange function very nicely but denies people any interest earnings. (Checking accounts did not earn interest before 1980.)

Over the last few decades, especially as a result of high interest rates and high inflation in the late 1970s, people sought and found ways of holding their financial assets in ways that earn interest and that can easily be converted to money. For example, it is now possible to transfer money from your savings account to your checking account using an automated teller machine (ATM), and then to withdraw cash from your checking account. Thus, many types of savings accounts are easily converted into currency.

Economists refer to the ease with which an asset can be converted into currency as the asset’s liquidityThe ease with which an asset can be converted into currency.. Currency itself is perfectly liquid; you can always change two $5 bills for a $10 bill. Checkable deposits are almost perfectly liquid; you can easily cash a check or visit an ATM. An office building, however, is highly illiquid. It can be converted to money only by selling it, a time-consuming and costly process.

As financial assets other than checkable deposits have become more liquid, economists have had to develop broader measures of money that would correspond to economic activity. In the United States, the final arbiter of what is and what is not measured as money is the Federal Reserve System. Because it is difficult to determine what (and what not) to measure as money, the Fed reports several different measures of money, including M1 and M2.

M1The narrowest of the Fed’s money supply definitions that includes currency in circulation, checkable deposits, and traveler’s checks. is the narrowest of the Fed’s money supply definitions. It includes currency in circulation, checkable deposits, and traveler’s checks. M2A broader measure of the money supply than M1 that includes M1 and other deposits. is a broader measure of the money supply than M1. It includes M1 and other deposits such as small savings accounts (less than $100,000), as well as accounts such as money market mutual funds (MMMFs) that place limits on the number or the amounts of the checks that can be written in a certain period.

M2 is sometimes called the broadly defined money supply, while M1 is the narrowly defined money supply. The assets in M1 may be regarded as perfectly liquid; the assets in M2 are highly liquid, but somewhat less liquid than the assets in M1. Even broader measures of the money supply include large time-deposits, money market mutual funds held by institutions, and other assets that are somewhat less liquid than those in M2. Figure 9.1 "The Two Ms: January 2012" shows the composition of M1 and M2 in October 2010.

Figure 9.1 The Two Ms: January 2012

M1, the narrowest definition of the money supply, includes assets that are perfectly liquid. M2 provides a broader measure of the money supply and includes somewhat less liquid assets. Amounts represent money supply data in billions of dollars for January 2012, seasonally adjusted.

Source: Federal Reserve Statistical Release H.6, Tables 3 and 4 (February 16, 2012). Amounts are in billions of dollars for January 2012, seasonally adjusted.

With all the operational definitions of money available, which one should we use? Economists generally answer that question by asking another: Which measure of money is most closely related to real GDP and the price level? As that changes, so must the definition of money.

In 1980, the Fed decided that changes in the ways people were managing their money made M1 useless for policy choices. Indeed, the Fed now pays little attention to M2 either. It has largely given up tracking a particular measure of the money supply. The choice of what to measure as money remains the subject of continuing research and considerable debate.

Case in Point: Fiat-less Money

“We don’t have a currency of our own,” proclaimed Nerchivan Barzani, the Kurdish regional government’s prime minister in a news interview in 2003. But, even without official recognition by the government, the so-called “Swiss” dinar certainly seemed to function as a fiat money. Here is how the Kurdish area of northern Iraq, during the period between the Gulf War in 1991 and the fall of Saddam Hussein in 2003, came to have its own currency, despite the pronouncement of its prime minister to the contrary.

After the Gulf War, the northern, mostly Kurdish area of Iraq was separated from the rest of Iraq though the enforcement of the no-fly-zone. Because of United Nations sanctions that barred the Saddam Hussein regime in the south from continuing to import currency from Switzerland, the central bank of Iraq announced it would replace the “Swiss” dinars, so named because they had been printed in Switzerland, with locally printed currency, which became known as “Saddam” dinars. Iraqi citizens in southern Iraq were given three weeks to exchange their old dinars for the new ones. In the northern part of Iraq, citizens could not exchange their notes and so they simply continued to use the old ones.

And so it was that the “Swiss” dinar for a period of about 10 years, even without government backing or any law establishing it as legal tender, served as northern Iraq’s fiat money. Economists use the word “fiat,” which in Latin means “let it be done,” to describe money that has no intrinsic value. Such forms of money usually get their value because a government or authority has declared them to be legal tender, but, as this story shows, it does not really require much “fiat” for a convenient, in-and-of-itself worthless, medium of exchange to evolve.

What happened to both the “Swiss” and “Saddam” dinars? After the Coalition Provisional Authority (CPA) assumed control of all of Iraq, Paul Bremer, then head of the CPA, announced that a new Iraqi dinar would be exchanged for both of the existing currencies over a three-month period ending in January 2004 at a rate that implied that one “Swiss” dinar was valued at 150 “Saddam” dinars. Because Saddam Hussein’s regime had printed many more “Saddam” dinars over the 10-year period, while no “Swiss” dinars had been printed, and because the cheap printing of the “Saddam” dinars made them easy to counterfeit, over the decade the “Swiss” dinars became relatively more valuable and the exchange rate that Bremer offered about equalized the purchasing power of the two currencies. For example, it took about 133 times as many “Saddam” dinars as “Swiss” dinars to buy a man’s suit in Iraq at the time. The new notes, sometimes called “Bremer” dinars, were printed in Britain and elsewhere and flown into Iraq on 22 flights using Boeing 747s and other large aircraft. In both the northern and southern parts of Iraq, citizens turned in their old dinars for the new ones, suggesting at least more confidence at that moment in the “Bremer” dinar than in either the “Saddam” or “Swiss” dinars.

Sources: Mervyn A. King, “The Institutions of Monetary Policy” (lecture, American Economics Association Annual Meeting, San Diego, January 4, 2004), available at http://www.bankofengland.co.uk/publications/Documents/speeches/2004/speech208.pdf; Hal R. Varian, “Paper Currency Can Have Value without Government Backing, but Such Backing Adds Substantially to Its Value,” New York Times, January 15, 2004, p. C2.

Banks and Other Financial Intermediaries

An institution that amasses funds from one group and makes them available to another is called a financial intermediaryAn institution that amasses funds from one group and makes them available to another.. A pension fund is an example of a financial intermediary. Workers and firms place earnings in the fund for their retirement; the fund earns income by lending money to firms or by purchasing their stock. The fund thus makes retirement saving available for other spending. Insurance companies are also financial intermediaries, because they lend some of the premiums paid by their customers to firms for investment. Mutual funds make money available to firms and other institutions by purchasing their initial offerings of stocks or bonds.

Banks play a particularly important role as financial intermediaries. Banks accept depositors’ money and lend it to borrowers. With the interest they earn on their loans, banks are able to pay interest to their depositors, cover their own operating costs, and earn a profit, all the while maintaining the ability of the original depositors to spend the funds when they desire to do so. One key characteristic of banks is that they offer their customers the opportunity to open checking accounts, thus creating checkable deposits. These functions define a bankA financial intermediary that accepts deposits, makes loans, and offers checking accounts., which is a financial intermediary that accepts deposits, makes loans, and offers checking accounts.

Over time, some nonbank financial intermediaries have become more and more like banks. For example, brokerage firms usually offer customers interest-earning accounts and make loans. They now allow their customers to write checks on their accounts.

The fact that banks account for a declining share of U.S. financial assets alarms some observers. We will see that banks are more tightly regulated than are other financial institutions; one reason for that regulation is to maintain control over the money supply. Other financial intermediaries do not face the same regulatory restrictions as banks. Indeed, their relative freedom from regulation is one reason they have grown so rapidly. As other financial intermediaries become more important, central authorities begin to lose control over the money supply.

The declining share of financial assets controlled by “banks” began to change in 2008. Many of the nation’s largest investment banks—financial institutions that provided services to firms but were not regulated as commercial banks—began having serious financial difficulties as a result of their investments tied to home mortgage loans. As home prices in the United States began falling, many of those mortgage loans went into default. Investment banks that had made substantial purchases of securities whose value was ultimately based on those mortgage loans themselves began failing. Bear Stearns, one of the largest investment banks in the United States, required federal funds to remain solvent. Another large investment bank, Lehman Brothers, failed. In an effort to avoid a similar fate, several other investment banks applied for status as ordinary commercial banks subject to the stringent regulation those institutions face. One result of the terrible financial crisis that crippled the U.S. and other economies in 2008 may be greater control of the money supply by the Fed.

Bank Finance and a Fractional Reserve System

Bank finance lies at the heart of the process through which money is created. To understand money creation, we need to understand some of the basics of bank finance.

Banks accept deposits and issue checks to the owners of those deposits. Banks use the money collected from depositors to make loans. The bank’s financial picture at a given time can be depicted using a simplified balance sheetA financial statement showing assets, liabilities, and net worth., which is a financial statement showing assets, liabilities, and net worth. AssetsAnything of value. are anything of value. LiabilitiesObligations to other parties. are obligations to other parties. Net worthAssets less liabilities. equals assets less liabilities. All these are given dollar values in a firm’s balance sheet. The sum of liabilities plus net worth therefore must equal the sum of all assets. On a balance sheet, assets are listed on the left, liabilities and net worth on the right.

The main way that banks earn profits is through issuing loans. Because their depositors do not typically all ask for the entire amount of their deposits back at the same time, banks lend out most of the deposits they have collected—to companies seeking to expand their operations, to people buying cars or homes, and so on. Banks keep only a fraction of their deposits as cash in their vaults and in deposits with the Fed. These assets are called reservesBank assets held as cash in vaults and in deposits with the Federal Reserve.. Banks lend out the rest of their deposits. A system in which banks hold reserves whose value is less than the sum of claims outstanding on those reserves is called a fractional reserve banking systemSystem in which banks hold reserves whose value is less than the sum of claims outstanding on those reserves..

Table 9.1 "The Consolidated Balance Sheet for U.S. Commercial Banks, January 2012" shows a consolidated balance sheet for commercial banks in the United States for January 2012. Banks hold reserves against the liabilities represented by their checkable deposits. Notice that these reserves were a small fraction of total deposit liabilities of that month. Most bank assets are in the form of loans.

In the next section, we will learn that money is created when banks issue loans.

Money Creation

To understand the process of money creation today, let us create a hypothetical system of banks. We will focus on three banks in this system: Acme Bank, Bellville Bank, and Clarkston Bank. Assume that all banks are required to hold reserves equal to 10% of their checkable deposits. The quantity of reserves banks are required to hold is called required reservesThe quantity of reserves banks are required to hold.. The reserve requirement is expressed as a required reserve ratioThe ratio of reserves to checkable deposits a bank must maintain.; it specifies the ratio of reserves to checkable deposits a bank must maintain. Banks may hold reserves in excess of the required level; such reserves are called excess reservesReserves in excess of the required level.. Excess reserves plus required reserves equal total reserves.

Because banks earn relatively little interest on their reserves held on deposit with the Federal Reserve, we shall assume that they seek to hold no excess reserves. When a bank’s excess reserves equal zero, it is loaned upWhen a bank’s excess reserves equal zero.. Finally, we shall ignore assets other than reserves and loans and deposits other than checkable deposits. To simplify the analysis further, we shall suppose that banks have no net worth; their assets are equal to their liabilities.

Let us suppose that every bank in our imaginary system begins with $1,000 in reserves, $9,000 in loans outstanding, and $10,000 in checkable deposit balances held by customers. The balance sheet for one of these banks, Acme Bank, is shown in Table 9.2 "A Balance Sheet for Acme Bank". The required reserve ratio is 0.1: Each bank must have reserves equal to 10% of its checkable deposits. Because reserves equal required reserves, excess reserves equal zero. Each bank is loaned up.

Acme Bank, like every other bank in our hypothetical system, initially holds reserves equal to the level of required reserves. Now suppose one of Acme Bank’s customers deposits $1,000 in cash in a checking account. The money goes into the bank’s vault and thus adds to reserves. The customer now has an additional $1,000 in his or her account. Two versions of Acme’s balance sheet are given here. The first shows the changes brought by the customer’s deposit: reserves and checkable deposits rise by $1,000. The second shows how these changes affect Acme’s balances. Reserves now equal $2,000 and checkable deposits equal $11,000. With checkable deposits of $11,000 and a 10% reserve requirement, Acme is required to hold reserves of $1,100. With reserves equaling $2,000, Acme has $900 in excess reserves.

At this stage, there has been no change in the money supply. When the customer brought in the $1,000 and Acme put the money in the vault, currency in circulation fell by $1,000. At the same time, the $1,000 was added to the customer’s checking account balance, so the money supply did not change.

Figure 9.2

Because Acme earns only a low interest rate on its excess reserves, we assume it will try to loan them out. Suppose Acme lends the $900 to one of its customers. It will make the loan by crediting the customer’s checking account with $900. Acme’s outstanding loans and checkable deposits rise by $900. The $900 in checkable deposits is new money; Acme created it when it issued the $900 loan. Now you know where money comes from—it is created when a bank issues a loan.

Figure 9.3

Presumably, the customer who borrowed the $900 did so in order to spend it. That customer will write a check to someone else, who is likely to bank at some other bank. Suppose that Acme’s borrower writes a check to a firm with an account at Bellville Bank. In this set of transactions, Acme’s checkable deposits fall by $900. The firm that receives the check deposits it in its account at Bellville Bank, increasing that bank’s checkable deposits by $900. Bellville Bank now has a check written on an Acme account. Bellville will submit the check to the Fed, which will reduce Acme’s deposits with the Fed—its reserves—by $900 and increase Bellville’s reserves by $900.

Figure 9.4

Notice that Acme Bank emerges from this round of transactions with $11,000 in checkable deposits and $1,100 in reserves. It has eliminated its excess reserves by issuing the loan for $900; Acme is now loaned up. Notice also that from Acme’s point of view, it has not created any money! It merely took in a $1,000 deposit and emerged from the process with $1,000 in additional checkable deposits.

The $900 in new money Acme created when it issued a loan has not vanished—it is now in an account in Bellville Bank. Like the magician who shows the audience that the hat from which the rabbit appeared was empty, Acme can report that it has not created any money. There is a wonderful irony in the magic of money creation: banks create money when they issue loans, but no one bank ever seems to keep the money it creates. That is because money is created within the banking system, not by a single bank.

The process of money creation will not end there. Let us go back to Bellville Bank. Its deposits and reserves rose by $900 when the Acme check was deposited in a Bellville account. The $900 deposit required an increase in required reserves of $90. Because Bellville’s reserves rose by $900, it now has $810 in excess reserves. Just as Acme lent the amount of its excess reserves, we can expect Bellville to lend this $810. The next set of balance sheets shows this transaction. Bellville’s loans and checkable deposits rise by $810.

Figure 9.5

The $810 that Bellville lent will be spent. Let us suppose it ends up with a customer who banks at Clarkston Bank. Bellville’s checkable deposits fall by $810; Clarkston’s rise by the same amount. Clarkston submits the check to the Fed, which transfers the money from Bellville’s reserve account to Clarkston’s. Notice that Clarkston’s deposits rise by $810; Clarkston must increase its reserves by $81. But its reserves have risen by $810, so it has excess reserves of $729.

Figure 9.6

Notice that Bellville is now loaned up. And notice that it can report that it has not created any money either! It took in a $900 deposit, and its checkable deposits have risen by that same $900. The $810 it created when it issued a loan is now at Clarkston Bank.

The process will not end there. Clarkston will lend the $729 it now has in excess reserves, and the money that has been created will end up at some other bank, which will then have excess reserves—and create still more money. And that process will just keep going as long as there are excess reserves to pass through the banking system in the form of loans. How much will ultimately be created by the system as a whole? With a 10% reserve requirement, each dollar in reserves backs up $10 in checkable deposits. The $1,000 in cash that Acme’s customer brought in adds $1,000 in reserves to the banking system. It can therefore back up an additional $10,000! In just the three banks we have shown, checkable deposits have risen by $2,710 ($1,000 at Acme, $900 at Bellville, and $810 at Clarkston). Additional banks in the system will continue to create money, up to a maximum of $7,290 among them. Subtracting the original $1,000 that had been a part of currency in circulation, we see that the money supply could rise by as much as $9,000.

The Deposit Multiplier

We can relate the potential increase in the money supply to the change in reserves that created it using the deposit multiplierThe ratio of the maximum possible change in checkable deposits (∆D) to the change in reserves (∆R). (m_d), which equals the ratio of the maximum possible change in checkable deposits (∆D) to the change in reserves (∆R). In our example, the deposit multiplier was 10:

To see how the deposit multiplier m_d is related to the required reserve ratio, we use the fact that if banks in the economy are loaned up, then reserves, R, equal the required reserve ratio (rrr) times checkable deposits, D:

A change in reserves produces a change in loans and a change in checkable deposits. Once banks are fully loaned up, the change in reserves, ∆R, will equal the required reserve ratio times the change in deposits, ∆D:

Solving for ∆D, we have

Dividing both sides by ∆R, we see that the deposit multiplier, m_d, is 1/rrr:

The deposit multiplier is thus given by the reciprocal of the required reserve ratio. With a required reserve ratio of 0.1, the deposit multiplier is 10. A required reserve ratio of 0.2 would produce a deposit multiplier of 5. The higher the required reserve ratio, the lower the deposit multiplier.

Actual increases in checkable deposits will not be nearly as great as suggested by the deposit multiplier. That is because the artificial conditions of our example are not met in the real world. Some banks hold excess reserves, customers withdraw cash, and some loan proceeds are not spent. Each of these factors reduces the degree to which checkable deposits are affected by an increase in reserves. The basic mechanism, however, is the one described in our example, and it remains the case that checkable deposits increase by a multiple of an increase in reserves.

The entire process of money creation can work in reverse. When you withdraw cash from your bank, you reduce the bank’s reserves. Just as a deposit at Acme Bank increases the money supply by a multiple of the original deposit, your withdrawal reduces the money supply by a multiple of the amount you withdraw. And just as money is created when banks issue loans, it is destroyed as the loans are repaid. A loan payment reduces checkable deposits; it thus reduces the money supply.

Suppose, for example, that the Acme Bank customer who borrowed the $900 makes a $100 payment on the loan. Only part of the payment will reduce the loan balance; part will be interest. Suppose $30 of the payment is for interest, while the remaining $70 reduces the loan balance. The effect of the payment on Acme’s balance sheet is shown below. Checkable deposits fall by $100, loans fall by $70, and net worth rises by the amount of the interest payment, $30.

Similar to the process of money creation, the money reduction process decreases checkable deposits by, at most, the amount of the reduction in deposits times the deposit multiplier.

Figure 9.7

The Regulation of Banks

Banks are among the most heavily regulated of financial institutions. They are regulated in part to protect individual depositors against corrupt business practices. Banks are also susceptible to crises of confidence. Because their reserves equal only a fraction of their deposit liabilities, an effort by customers to get all their cash out of a bank could force it to fail. A few poorly managed banks could create such a crisis, leading people to try to withdraw their funds from well-managed banks. Another reason for the high degree of regulation is that variations in the quantity of money have important effects on the economy as a whole, and banks are the institutions through which money is created.

Regulation in Response to Financial Crises

In the aftermath of the Great Depression and the banking crisis that accompanied it, laws were passed to try to make the banking system safer. The Glass-Steagall Act of that period created the FDIC and the separation between commercial banks and investment banks. Over time, the financial system in the United States and in other countries began to change, and in 1999, a law was passed in the United States that essentially repealed the part of the Glass-Steagall Act that had created the separation between commercial and investment banking. Proponents of eliminating the separation between the two types of banks argued that banks could better diversify their portfolios if allowed to participate in other parts of the financial markets and that banks in other countries operated without such a separation.

Similar to the reaction to the banking crisis of the 1930s, the financial crisis of 2008 and the Great Recession led to calls for financial market reform. The result was the Dodd-Frank Wall Street Reform and Consumer Protection Act, usually referred to as the Dodd-Frank Act, which was passed in July 2010. More than 2,000 pages in length, the regulations to implement most provisions of this act were set to take place over a nearly two-year period, with some provisions expected to take even longer to implement. This act created the Consumer Financial Protection Agency to oversee and regulate various aspects of consumer credit markets, such as credit card and bank fees and mortgage contracts. It also created the Financial Stability Oversight Council (FSOC) to assess risks for the entire financial industry. The FSOC can recommend that a nonbank financial firm, such as a hedge fund that is perhaps threatening the stability of the financial system (i.e., getting “too big to fail”), become regulated by the Federal Reserve. If such firms do become insolvent, a process of liquidation similar to what occurs when the FDIC takes over a bank can be applied. The Dodd-Frank Act also calls for implementation of the Volcker rule, which was named after the former chair of the Fed who argued the case. The Volcker rule is meant to ban banks from using depositors’ funds to engage in certain types of speculative investments to try to enhance the profits of the bank, at least partly reinstating the separation between commercial and investment banking that the Glass-Steagall Act had created. There are many other provisions in this wide-sweeping legislation that are designed to improve oversight of nonbank financial institutions, increase transparency in the operation of various forms of financial instruments, regulate credit rating agencies such as Moody’s and Standard & Poor’s, and so on. Given the lag time associated with fully implementing the legislation, it will probably be many years before its impact can be fully assessed.

Key Takeaways

• Banks are financial intermediaries that accept deposits, make loans, and provide checking accounts for their customers.
• Money is created within the banking system when banks issue loans; it is destroyed when the loans are repaid.
• An increase (decrease) in reserves in the banking system can increase (decrease) the money supply. The maximum amount of the increase (decrease) is equal to the deposit multiplier times the change in reserves; the deposit multiplier equals the reciprocal of the required reserve ratio.
• Bank deposits are insured and banks are heavily regulated.
• Similar to the passage of the Glass-Steagall Act during the Great Depression, the Dodd-Frank Act was the comprehensive financial reform legislation that responded to the financial crisis in 2008 and the Great Recession.

Try It!

1. Suppose Acme Bank initially has $10,000 in deposits, reserves of $2,000, and loans of $8,000. At a required reserve ratio of 0.2, is Acme loaned up? Show the balance sheet of Acme Bank at present.
2. Now suppose that an Acme Bank customer, planning to take cash on an extended college graduation trip to India, withdraws $1,000 from her account. Show the changes to Acme Bank’s balance sheet and Acme’s balance sheet after the withdrawal. By how much are its reserves now deficient?
3. Acme would probably replenish its reserves by reducing loans. This action would cause a multiplied contraction of checkable deposits as other banks lose deposits because their customers would be paying off loans to Acme. How large would the contraction be?

Case in Point: A Big Bank Goes Under

It was the darling of Wall Street—it showed rapid growth and made big profits. Washington Mutual, a savings and loan based in the state of Washington, was a relatively small institution whose CEO, Kerry K. Killinger, had big plans. He wanted to transform his little Seattle S&L into the Wal-Mart of banks.

Mr. Killinger began pursuing a relatively straightforward strategy. He acquired banks in large cities such as Chicago and Los Angeles. He acquired banks up and down the east and west coasts. He aggressively extended credit to low-income individuals and families—credit cards, car loans, and mortgages. In making mortgage loans to low-income families, WaMu, as the bank was known, quickly became very profitable. But it was exposing itself to greater and greater risk, according to the New York Times.

Housing prices in the United States more than doubled between 1997 and 2007. During that time, loans to even low-income households were profitable. But, as housing prices began falling in 2007, banks such as WaMu began to experience losses as homeowners began to walk away from houses whose values suddenly fell below their outstanding mortgages. WaMu began losing money in 2007 as housing prices began falling. The company had earned $3.6 billion in 2006, and swung to a loss of $67 million in 2007, according to the Puget Sound Business Journal. Mr. Killinger was ousted by the board early in September of 2008. The bank failed later that month. It was the biggest bank failure in the history of the United States.

The Federal Deposit Insurance Corporation (FDIC) had just rescued another bank, IndyMac, which was only a tenth the size of WaMu, and would have done the same for WaMu if it had not been able to find a company to purchase it. But in this case, JPMorgan Chase agreed to take it over—its deposits, bank branches, and its troubled asset portfolio. The government and the Fed even negotiated the deal behind WaMu’s back! The then chief executive officer of the company, Alan H. Fishman, was reportedly flying from New York to Seattle when the deal was finalized.

The government was anxious to broker a deal that did not require use of the FDIC’s depleted funds following IndyMac’s collapse. But it would have done so if a buyer had not been found. As the FDIC reports on its Web site: “Since the FDIC’s creation in 1933, no depositor has ever lost even one penny of FDIC-insured funds.”

Sources: Eric Dash and Andrew Ross Sorkin, “Government Seizes WaMu and Sells Some Assets,” New York Times, September 25, 2008, p. A1; Kirsten Grind, “Insiders Detail Reasons for WaMu’s Failure,” Puget Sound Business Journal, January 23, 2009; and FDIC Web site at https://www.fdic.gov/edie/fdic_info.html.

Answer to Try It! Problem

1. Acme Bank is loaned up, since $2,000/$10,000 = 0.2, which is the required reserve ratio. Acme’s balance sheet is:

   

2. Acme Bank’s balance sheet after losing $1,000 in deposits:

   

   Required reserves are deficient by $800. Acme must hold 20% of its deposits, in this case $\text{\$}\mathrm{1,800}\text{ (}0.2\times \text{ \$}\mathrm{9,000}=\text{\$}\mathrm{1,800}\text{)}$, as reserves, but it has only $1,000 in reserves at the moment.

3. The contraction in checkable deposits would be

   ∆D = (1/0.2) × (−$1,000) = −$5,000

Structure of the Fed

In creating the Fed, Congress determined that a central bank should be as independent of the government as possible. It also sought to avoid too much centralization of power in a single institution. These potentially contradictory goals of independence and decentralized power are evident in the Fed’s structure and in the continuing struggles between Congress and the Fed over possible changes in that structure.

In an effort to decentralize power, Congress designed the Fed as a system of 12 regional banks, as shown in Figure 9.8 "The 12 Federal Reserve Districts and the Cities Where Each Bank Is Located". Each of these banks operates as a kind of bankers’ cooperative; the regional banks are owned by the commercial banks in their districts that have chosen to be members of the Fed. The owners of each Federal Reserve bank select the board of directors of that bank; the board selects the bank’s president.

Figure 9.8 The 12 Federal Reserve Districts and the Cities Where Each Bank Is Located

Several provisions of the Federal Reserve Act seek to maintain the Fed’s independence. The board of directors for the entire Federal Reserve System is called the Board of Governors. The seven members of the board are appointed by the president of the United States and confirmed by the Senate. To ensure a large measure of independence from any one president, the members of the Board of Governors have 14-year terms. One member of the board is selected by the president of the United States to serve as chairman for a four-year term.

As a further means of ensuring the independence of the Fed, Congress authorized it to buy and sell federal government bonds. This activity is a profitable one that allows the Fed to pay its own bills. The Fed is thus not dependent on a Congress that might otherwise be tempted to force a particular set of policies on it. The Fed is limited in the profits it is allowed to earn; its “excess” profits are returned to the Treasury.

It is important to recognize that the Fed is technically not part of the federal government. Members of the Board of Governors do not legally have to answer to Congress, the president, or anyone else. The president and members of Congress can certainly try to influence the Fed, but they cannot order it to do anything. Congress, however, created the Fed. It could, by passing another law, abolish the Fed’s independence. The Fed can maintain its independence only by keeping the support of Congress—and that sometimes requires being responsive to the wishes of Congress.

In recent years, Congress has sought to increase its oversight of the Fed. The chairman of the Federal Reserve Board is required to report to Congress twice each year on its monetary policy, the set of policies that the central bank can use to influence economic activity.

Powers of the Fed

The Fed’s principal powers stem from its authority to conduct monetary policy. It has three main policy tools: setting reserve requirements, operating the discount window and other credit facilities, and conducting open-market operations.

Open-Market Operations

The Fed’s ability to buy and sell federal government bonds has proved to be its most potent policy tool. A bondA promise by the issuer of the bond to pay the owner of the bond a payment or a series of payments on a specific date or dates. is a promise by the issuer of the bond (in this case the federal government) to pay the owner of the bond a payment or a series of payments on a specific date or dates. The buying and selling of federal government bonds by the Fed are called open-market operationsThe buying and selling of federal government bonds by the Fed.. When the Fed buys or sells government bonds, it adds or subtracts reserves from the banking system. Such changes affect the money supply.

Suppose the Fed buys a government bond in the open market. It writes a check on its own account to the seller of the bond. When the seller deposits the check at a bank, the bank submits the check to the Fed for payment. The Fed “pays” the check by crediting the bank’s account at the Fed, so the bank has more reserves.

The Fed’s purchase of a bond can be illustrated using a balance sheet. Suppose the Fed buys a bond for $1,000 from one of Acme Bank’s customers. When that customer deposits the check at Acme, checkable deposits will rise by $1,000. The check is written on the Federal Reserve System; the Fed will credit Acme’s account. Acme’s reserves thus rise by $1,000. With a 10% reserve requirement, that will create $900 in excess reserves and set off the same process of money expansion as did the cash deposit we have already examined. The difference is that the Fed’s purchase of a bond created new reserves with the stroke of a pen, where the cash deposit created them by removing $1,000 from currency in circulation. The purchase of the $1,000 bond by the Fed could thus increase the money supply by as much as $10,000, the maximum expansion suggested by the deposit multiplier.

Figure 9.9

Where does the Fed get $1,000 to purchase the bond? It simply creates the money when it writes the check to purchase the bond. On the Fed’s balance sheet, assets increase by $1,000 because the Fed now has the bond; bank deposits with the Fed, which represent a liability to the Fed, rise by $1,000 as well.

When the Fed sells a bond, it gives the buyer a federal government bond that it had previously purchased and accepts a check in exchange. The bank on which the check was written will find its deposit with the Fed reduced by the amount of the check. That bank’s reserves and checkable deposits will fall by equal amounts; the reserves, in effect, disappear. The result is a reduction in the money supply. The Fed thus increases the money supply by buying bonds; it reduces the money supply by selling them.

Figure 9.10 "The Fed and the Flow of Money in the Economy" shows how the Fed influences the flow of money in the economy. Funds flow from the public—individuals and firms—to banks as deposits. Banks use those funds to make loans to the public—to individuals and firms. The Fed can influence the volume of bank lending by buying bonds and thus injecting reserves into the system. With new reserves, banks will increase their lending, which creates still more deposits and still more lending as the deposit multiplier goes to work. Alternatively, the Fed can sell bonds. When it does, reserves flow out of the system, reducing bank lending and reducing deposits.

Figure 9.10 The Fed and the Flow of Money in the Economy

Individuals and firms (the public) make deposits in banks; banks make loans to individuals and firms. The Fed can buy bonds to inject new reserves into the system, thus increasing bank lending, which creates new deposits, creating still more lending as the deposit multiplier goes to work. Alternatively, the Fed can sell bonds, withdrawing reserves from the system, thus reducing bank lending and reducing total deposits.

The Fed’s purchase or sale of bonds is conducted by the Open Market Desk at the Federal Reserve Bank of New York, one of the 12 district banks. Traders at the Open Market Desk are guided by policy directives issued by the Federal Open Market Committee (FOMC). The FOMC consists of the seven members of the Board of Governors plus five regional bank presidents. The president of the New York Federal Reserve Bank serves as a member of the FOMC; the other 11 bank presidents take turns filling the remaining four seats.

The FOMC meets eight times per year to chart the Fed’s monetary policies. In the past, FOMC meetings were closed, with no report of the committee’s action until the release of the minutes six weeks after the meeting. Faced with pressure to open its proceedings, the Fed began in 1994 issuing a report of the decisions of the FOMC immediately after each meeting.

In practice, the Fed sets targets for the federal funds rate. To achieve a lower federal funds rate, the Fed goes into the open market buying securities and thus increasing the money supply. When the Fed raises its target rate for the federal funds rate, it sells securities and thus reduces the money supply.

Traditionally, the Fed has bought and sold short-term government securities; however, in dealing with the condition of the economy in 2009, wherein the Fed has already set the target for the federal funds rate at near zero, the Fed has announced that it will also be buying longer term government securities. In so doing, it hopes to influence longer term interest rates, such as those related to mortgages.

Key Takeaways

• The Fed, the central bank of the United States, acts as a bank for other banks and for the federal government. It also regulates banks, sets monetary policy, and maintains the stability of the financial system.
• The Fed sets reserve requirements and the discount rate and conducts open-market operations. Of these tools of monetary policy, open-market operations are the most important.
• Starting in 2007, the Fed began creating additional credit facilities to help stabilize the financial system.
• The Fed creates new reserves and new money when it purchases bonds. It destroys reserves and thus reduces the money supply when it sells bonds.

Try It!

Suppose the Fed sells $8 million worth of bonds.

1. How do bank reserves change?
2. Will the money supply increase or decrease?
3. What is the maximum possible change in the money supply if the required reserve ratio is 0.2?

Case in Point: Fed Supports the Financial System by Creating New Credit Facilities

Well before most of the public became aware of the precarious state of the U.S. financial system, the Fed began to see signs of growing financial strains and to act on reducing them. In particular, the Fed saw that short-term interest rates that are often quite close to the federal funds rate began to rise markedly above it. The widening spread was alarming, because it suggested that lender confidence was declining, even for what are generally considered low-risk loans. Commercial paper, in which large companies borrow funds for a period of about a month to manage their cash flow, is an example. Even companies with high credit ratings were having to pay unusually high interest rate premiums in order to get funding, or in some cases could not get funding at all.

To deal with the drying up of credit markets, in late 2007 the Fed began to create an alphabet soup of new credit facilities. Some of these were offered in conjunction with the Department of the Treasury, which had more latitude in terms of accepting some credit risk. The facilities differed in terms of collateral used, the duration of the loan, which institutions were eligible to borrow, and the cost to the borrower. For example, the Primary Dealer Credit Facility (PDCF) allowed primary dealers (i.e., those financial institutions that normally handle the Fed’s open market operations) to obtain overnight loans. The Term Asset-Backed Securities Loan Facility (TALF) allowed a wide range of companies to borrow, using the primary dealers as conduits, based on qualified asset-backed securities related to student, auto, credit card, and small business debt, for a three-year period. Most of these new facilities were designed to be temporary. Starting in 2009 and 2010, the Fed began closing a number of them or at least preventing them from issuing new loans.

The common goal of all of these various credit facilities was to increase liquidity in order to stimulate private spending. For example, these credit facilities encouraged banks to pare down their excess reserves (which grew enormously as the financial crisis unfolded and the economy deteriorated) and to make more loans. In the words of Fed Chairman Ben Bernanke:

“Liquidity provision by the central bank reduces systemic risk by assuring market participants that, should short-term investors begin to lose confidence, financial institutions will be able to meet the resulting demands for cash without resorting to potentially destabilizing fire sales of assets. Moreover, backstopping the liquidity needs of financial institutions reduces funding stresses and, all else equal, should increase the willingness of those institutions to lend and make markets.”

The legal authority for most of these new credit facilities came from a particular section of the Federal Reserve Act that allows the Board of Governors “in unusual and exigent circumstances” to extend credit to a wide range of market players.

Sources: Ben S. Bernanke, “The Crisis and the Policy Response” (Stemp Lecture, London School of Economics, London, England, January 13, 2009); Richard DiCecio and Charles S. Gascon, “New Monetary Policy Tools?” Federal Reserve Bank of St. Louis Monetary Trends, May 2008; Federal Reserve Board of Governors Web site at http://www.federalreserve.gov/monetarypolicy/default.htm.

Answer to Try It! Problem

1. Bank reserves fall by $8 million.
2. The money supply decreases.
3. The maximum possible decrease is $40 million, since ∆D = (1/0.2) × (−$8 million) = −$40 million.

The Bond Market

In their daily operations and in pursuit of new projects, institutions such as firms and governments often borrow. They may seek funds from a bank. Many institutions, however, obtain credit by selling bonds. The federal government is one institution that issues bonds. A local school district might sell bonds to finance the construction of a new school. Your college or university has probably sold bonds to finance new buildings on campus. Firms often sell bonds to finance expansion. The market for bonds is an enormously important one.

When an institution sells a bond, it obtains the price paid for the bond as a kind of loan. The institution that issues the bond is obligated to make payments on the bond in the future. The interest rate is determined by the price of the bond. To understand these relationships, let us look more closely at bond prices and interest rates.

Bond Prices and Interest Rates

Suppose the manager of a manufacturing company needs to borrow some money to expand the factory. The manager could do so in the following way: he or she prints, say, 500 pieces of paper, each bearing the company’s promise to pay the bearer $1,000 in a year. These pieces of paper are bonds, and the company, as the issuer, promises to make a single payment. The manager then offers these bonds for sale, announcing that they will be sold to the buyers who offer the highest prices. Suppose the highest price offered is $950, and all the bonds are sold at that price. Each bond is, in effect, an obligation to repay buyers $1,000. The buyers of the bonds are being paid $50 for the service of lending $950 for a year.

The $1,000 printed on each bond is the face value of the bondThe amount the issuer of a bond will have to pay on the maturity date.; it is the amount the issuer will have to pay on the maturity dateThe date when a bond matures, or comes due. of the bond—the date when the loan matures, or comes due. The $950 at which they were sold is their price. The difference between the face value and the price is the amount paid for the use of the money obtained from selling the bond.

An interest ratePayment made for the use of money, expressed as a percentage of the amount borrowed. is the payment made for the use of money, expressed as a percentage of the amount borrowed. Bonds you sold command an interest rate equal to the difference between the face value and the bond price, divided by the bond price, and then multiplied by 100 to form a percentage:

Equation 10.1

$$\frac{\text{Face value}-\text{bond price}}{\text{Bond price}}\times 100=\text{interest rate}$$

At a price of $950, the interest rate is 5.3%

$$\frac{\text{\$}\mathrm{1,000}-\text{\$}950}{\text{\$}950}\times 100=5.3\%$$

The interest rate on any bond is determined by its price. As the price falls, the interest rate rises. Suppose, for example, that the best price the manager can get for the bonds is $900. Now the interest rate is 11.1%. A price of $800 would mean an interest rate of 25%; $750 would mean an interest rate of 33.3%; a price of $500 translates into an interest rate of 100%. The lower the price of a bond relative to its face value, the higher the interest rate.

Bonds in the real world are more complicated than the piece of paper in our example, but their structure is basically the same. They have a face value (usually an amount between $1,000 and $100,000) and a maturity date. The maturity date might be three months from the date of issue; it might be 30 years.

Whatever the period until it matures, and whatever the face value of the bond may be, its issuer will attempt to sell the bond at the highest possible price. Buyers of bonds will seek the lowest prices they can obtain. Newly issued bonds are generally sold in auctions. Potential buyers bid for the bonds, which are sold to the highest bidders. The lower the price of the bond relative to its face value, the higher the interest rate.

Both private firms and government entities issue bonds as a way of raising funds. The original buyer need not hold the bond until maturity. Bonds can be resold at any time, but the price the bond will fetch at the time of resale will vary depending on conditions in the economy and the financial markets.

Figure 10.1 "The Bond Market" illustrates the market for bonds. Their price is determined by demand and supply. Buyers of newly issued bonds are, in effect, lenders. Sellers of newly issued bonds are borrowers—recall that corporations, the federal government, and other institutions sell bonds when they want to borrow money. Once a newly issued bond has been sold, its owner can resell it; a bond may change hands several times before it matures.

Figure 10.1 The Bond Market

The equilibrium price for bonds is determined where the demand and supply curves intersect. The initial solution here is a price of $950, implying an interest rate of 5.3%. An increase in borrowing, all other things equal, increases the supply of bonds to S₂ and forces the price of bonds down to $900. The interest rate rises to 11.1%.

Bonds are not exactly the same sort of product as, say, broccoli or some other good or service. Can we expect bonds to have the same kind of downward-sloping demand curves and upward-sloping supply curves we encounter for ordinary goods and services? Yes. Consider demand. At lower prices, bonds pay higher interest. That makes them more attractive to buyers of bonds and thus increases the quantity demanded. On the other hand, lower prices mean higher costs to borrowers—suppliers of bonds—and should reduce the quantity supplied. Thus, the negative relationship between price and quantity demanded and the positive relationship between price and quantity supplied suggested by conventional demand and supply curves holds true in the market for bonds.

If the quantity of bonds demanded is not equal to the quantity of bonds supplied, the price will adjust almost instantaneously to balance the two. Bond prices are perfectly flexible in that they change immediately to balance demand and supply. Suppose, for example, that the initial price of bonds is $950, as shown by the intersection of the demand and supply curves in Figure 10.1 "The Bond Market". We will assume that all bonds have equal risk and a face value of $1,000 and that they mature in one year. Now suppose that borrowers increase their borrowing by offering to sell more bonds at every interest rate. This increases the supply of bonds: the supply curve shifts to the right from S₁ to S₂. That, in turn, lowers the equilibrium price of bonds—to $900 in Figure 10.1 "The Bond Market". The lower price for bonds means a higher interest rate.

The Bond Market and Macroeconomic Performance

The connection between the bond market and the economy derives from the way interest rates affect aggregate demand. For example, investment is one component of aggregate demand, and interest rates affect investment. Firms are less likely to acquire new capital (that is, plant and equipment) if interest rates are high; they’re more likely to add capital if interest rates are low.Consumption may also be affected by changes in interest rates. For example, if interest rates fall, consumers can more easily obtain credit and thus are more likely to purchase cars and other durable goods. To simplify, we ignore this effect.

If bond prices fall, interest rates go up. Higher interest rates tend to discourage investment, so aggregate demand will fall. A fall in aggregate demand, other things unchanged, will mean fewer jobs and less total output than would have been the case with lower rates of interest. In contrast, an increase in the price of bonds lowers interest rates and makes investment in new capital more attractive. That change may boost investment and thus boost aggregate demand.

Figure 10.2 "Bond Prices and Macroeconomic Activity" shows how an event in the bond market can stimulate changes in the economy’s output and price level. In Panel (a), an increase in demand for bonds raises bond prices. Interest rates thus fall. Lower interest rates increase the quantity of investment demanded, shifting the aggregate demand curve to the right, from AD₁ to AD₂ in Panel (b). Real GDP rises from Y₁ to Y₂; the price level rises from P₁ to P₂. In Panel (c), an increase in the supply of bonds pushes bond prices down. Interest rates rise. The quantity of investment is likely to fall, shifting aggregate demand to the left, from AD₁ to AD₂ in Panel (d). Output and the price level fall from Y₁ to Y₂ and from P₁ to P₂, respectively. Assuming other determinants of aggregate demand remain unchanged, higher interest rates will tend to reduce aggregate demand and lower interest rates will tend to increase aggregate demand.

Figure 10.2 Bond Prices and Macroeconomic Activity

An increase in the demand for bonds to D₂ in Panel (a) raises the price of bonds to P^b₂, which lowers interest rates and boosts investment. That increases aggregate demand to AD₂ in Panel (b); real GDP rises to Y₂ and the price level rises to P₂.

An increase in the supply of bonds to S₂ lowers bond prices to P^b₂ in Panel (c) and raises interest rates. The higher interest rate, taken by itself, is likely to cause a reduction in investment and aggregate demand. AD₁ falls to AD₂, real GDP falls to Y₂, and the price level falls to P₂ in Panel (d).

In thinking about the impact of changes in interest rates on aggregate demand, we must remember that some events that change aggregate demand can affect interest rates. We will examine those events in subsequent chapters. Our focus in this chapter is on the way in which events that originate in financial markets affect aggregate demand.

Foreign Exchange Markets

Another financial market that influences macroeconomic variables is the foreign exchange marketA market in which currencies of different countries are traded for one another., a market in which currencies of different countries are traded for one another. Since changes in exports and imports affect aggregate demand and thus real GDP and the price level, the market in which currencies are traded has tremendous importance in the economy.

Foreigners who want to purchase goods and services or assets in the United States must typically pay for them with dollars. United States purchasers of foreign goods must generally make the purchase in a foreign currency. An Egyptian family, for example, exchanges Egyptian pounds for dollars in order to pay for admission to Disney World. A German financial investor purchases dollars to buy U.S. government bonds. A family from the United States visiting India, on the other hand, needs to obtain Indian rupees in order to make purchases there. A U.S. bank wanting to purchase assets in Mexico City first purchases pesos. These transactions are accomplished in the foreign exchange market.

The foreign exchange market is not a single location in which currencies are traded. The term refers instead to the entire array of institutions through which people buy and sell currencies. It includes a hotel desk clerk who provides currency exchange as a service to hotel guests, brokers who arrange currency exchanges worth billions of dollars, and governments and central banks that exchange currencies. Major currency dealers are linked by computers so that they can track currency exchanges all over the world.

Determining Exchange Rates

The rates at which most currencies exchange for one another are determined by demand and supply. How does the model of demand and supply operate in the foreign exchange market?

The demand curve for dollars relates the number of dollars buyers want to buy in any period to the exchange rate. An increase in the exchange rate means it takes more foreign currency to buy a dollar. A higher exchange rate, in turn, makes U.S. goods and services more expensive for foreign buyers and reduces the quantity they will demand. That is likely to reduce the quantity of dollars they demand. Foreigners thus will demand fewer dollars as the price of the dollar—the exchange rate—rises. Consequently, the demand curve for dollars is downward sloping, as in Figure 10.3 "Determining an Exchange Rate".

Figure 10.3 Determining an Exchange Rate

The equilibrium exchange rate is the rate at which the quantity of dollars demanded equals the quantity supplied. Here, equilibrium occurs at exchange rate E, at which Q dollars are exchanged per period.

The supply curve for dollars emerges from a similar process. When people and firms in the United States purchase goods, services, or assets in foreign countries, they must purchase the currency of those countries first. They supply dollars in exchange for foreign currency. The supply of dollars on the foreign exchange market thus reflects the degree to which people in the United States are buying foreign money at various exchange rates. A higher exchange rate means that a dollar trades for more foreign currency. In effect, the higher rate makes foreign goods and services cheaper to U.S. buyers, so U.S. consumers will purchase more foreign goods and services. People will thus supply more dollars at a higher exchange rate; we expect the supply curve for dollars to be upward sloping, as suggested in Figure 10.3 "Determining an Exchange Rate".

In addition to private individuals and firms that participate in the foreign exchange market, most governments participate as well. A government might seek to lower its exchange rate by selling its currency; it might seek to raise the rate by buying its currency. Although governments often participate in foreign exchange markets, they generally represent a very small share of these markets. The most important traders are private buyers and sellers of currencies.

Exchange Rates and Macroeconomic Performance

People purchase a country’s currency for two quite different reasons: to purchase goods or services in that country, or to purchase the assets of that country—its money, its capital, its stocks, its bonds, or its real estate. Both of these motives must be considered to understand why demand and supply in the foreign exchange market may change.

One thing that can cause the price of the dollar to rise, for example, is a reduction in bond prices in American markets. Figure 10.4 "Shifts in Demand and Supply for Dollars on the Foreign Exchange Market" illustrates the effect of this change. Suppose the supply of bonds in the U.S. bond market increases from S₁ to S₂ in Panel (a). Bond prices will drop. Lower bond prices mean higher interest rates. Foreign financial investors, attracted by the opportunity to earn higher returns in the United States, will increase their demand for dollars on the foreign exchange market in order to purchase U.S. bonds. Panel (b) shows that the demand curve for dollars shifts from D₁ to D₂. Simultaneously, U.S. financial investors, attracted by the higher interest rates at home, become less likely to make financial investments abroad and thus supply fewer dollars to exchange markets. The fall in the price of U.S. bonds shifts the supply curve for dollars on the foreign exchange market from S₁ to S₂, and the exchange rate rises from E₁ to E₂.

Figure 10.4 Shifts in Demand and Supply for Dollars on the Foreign Exchange Market

In Panel (a), an increase in the supply of bonds lowers bond prices to P^b₂ (and thus raises interest rates). Higher interest rates boost the demand and reduce the supply for dollars, increasing the exchange rate in Panel (b) to E₂. These developments in the bond and foreign exchange markets are likely to lead to a reduction in net exports and in investment, reducing aggregate demand from AD₁ to AD₂ in Panel (c). The price level in the economy falls to P₂, and real GDP falls from Y₁ to Y₂.

The higher exchange rate makes U.S. goods and services more expensive to foreigners, so it reduces exports. It makes foreign goods cheaper for U.S. buyers, so it increases imports. Net exports thus fall, reducing aggregate demand. Panel (c) shows that output falls from Y₁ to Y₂; the price level falls from P₁ to P₂. This development in the foreign exchange market reinforces the impact of higher interest rates we observed in Figure 10.2 "Bond Prices and Macroeconomic Activity", Panels (c) and (d). They not only reduce investment—they reduce net exports as well.

Key Takeaways

• A bond represents a borrower’s debt; bond prices are determined by demand and supply.
• The interest rate on a bond is negatively related to the price of the bond. As the price of a bond increases, the interest rate falls.
• An increase in the interest rate tends to decrease the quantity of investment demanded and, hence, to decrease aggregate demand. A decrease in the interest rate increases the quantity of investment demanded and aggregate demand.
• The demand for dollars on foreign exchange markets represents foreign demand for U.S. goods, services, and assets. The supply of dollars on foreign exchange markets represents U.S. demand for foreign goods, services, and assets. The demand for and the supply of dollars determine the exchange rate.
• A rise in U.S. interest rates will increase the demand for dollars and decrease the supply of dollars on foreign exchange markets. As a result, the exchange rate will increase and aggregate demand will decrease. A fall in U.S. interest rates will have the opposite effect.

Try It!

Suppose the supply of bonds in the U.S. market decreases. Show and explain the effects on the bond and foreign exchange markets. Use the aggregate demand/aggregate supply framework to show and explain the effects on investment, net exports, real GDP, and the price level.

Case in Point: Bill Gross’s Mea Culpa

In October 2011, bond fund manager Bill Gross sent out an extraordinary open letter titled “Mea Culpa.” He was taking the blame for the poor performance of Pimco Total Return Bond Fund, the huge fund he manages. After years of stellar performance, what had gone wrong?

Earlier in 2011, Mr. Gross announced that he would avoid U.S. Treasury bonds. He assumed that as the U.S. and other countries’ economies recovered, interest rates would begin to rise and, hence, U.S. bond prices would fall. When Mr. Gross pulled out of U.S. Treasuries, he used some of the cash to buy other types of debt, such as that of emerging markets. He also held onto some cash. He warned others to shun Treasuries as well.

However, as the financial situation in Europe weakened over worries about government debt in various European countries—starting with Greece and then spilling over to Portugal, Spain, Italy, and others—investors around the world flocked toward Treasuries, pushing Treasury bond prices up. It was a rally that Mr. Gross’s customers missed.

From where did the financial investors get the funds to buy Treasuries? In part, these funds were obtained from some of the same types of bonds that were then in the Pimco fund portfolio. As a result, the prices of bonds in the Pimco fund fell.

In the letter, Mr. Gross wrote, “The simple fact is that the portfolio at midyear was positioned for what we call a ‘New Normal’ developed world economy—2% real growth and 2% inflation. When growth estimates quickly changed it was obvious that I had misjudged the fly ball: E-CF or for nonbaseball aficionados—error centerfield.” In the fall of 2011, he shifted gears and began buying U.S. Treasuries, assuming that a weak global economy would keep interest rates low. He was foiled again, as interest rates started to rise a bit.

In the end, 2011 turned out to be a bad year for the fund, ranking poorly compared to its peers. But after many successful years, it retained its five-star rating by Morningstar in 2012. We must wait to see whether Mr. Gross will get his groove back. In the letter, he concluded, “There is no ‘quit’ in me or anyone else on the Pimco premises. The early morning and even midnight hours have gone up, not down, to match the increasing complexity of the global financial markets. The competitive fire burns even hotter. I/we respect our competition but we want to squash them each and every day…”

Source: “Bill Gross Apologizes to Pimco Fund Owners for ‘Bad Year,’” Los Angeles Times, October 14, 2011, online version.

Answer to Try It! Problem

If the supply of bonds decreases from S₁ to S₂, bond prices will rise from P^b₁ to P^b₂, as shown in Panel (a). Higher bond prices mean lower interest rates. Lower interest rates in the United States will make financial investments in the United States less attractive to foreigners. As a result, their demand for dollars will decrease from D₁ to D₂, as shown in Panel (b). Similarly, U.S. financial investors will look abroad for higher returns and thus supply more dollars to foreign exchange markets, shifting the supply curve from S₁ to S₂. Thus, the exchange rate will decrease. The quantity of investment rises due to the lower interest rates. Net exports rise because the lower exchange rate makes U.S. goods and services more attractive to foreigners, thus increasing exports, and makes foreign goods less attractive to U.S. buyers, thus reducing imports. Increases in investment and net exports imply a rightward shift in the aggregate demand curve from AD₁ to AD₂. Real GDP and the price level increase.