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Principles of Macroeconomics 2e

11.3 Shifts in Aggregate Supply

Principles of Macroeconomics 2e11.3 Shifts in Aggregate Supply
  1. Preface
  2. 1 Welcome to Economics!
    1. Introduction
    2. 1.1 What Is Economics, and Why Is It Important?
    3. 1.2 Microeconomics and Macroeconomics
    4. 1.3 How Economists Use Theories and Models to Understand Economic Issues
    5. 1.4 How To Organize Economies: An Overview of Economic Systems
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
  3. 2 Choice in a World of Scarcity
    1. Introduction to Choice in a World of Scarcity
    2. 2.1 How Individuals Make Choices Based on Their Budget Constraint
    3. 2.2 The Production Possibilities Frontier and Social Choices
    4. 2.3 Confronting Objections to the Economic Approach
    5. Key Terms
    6. Key Concepts and Summary
    7. Self-Check Questions
    8. Review Questions
    9. Critical Thinking Questions
    10. Problems
  4. 3 Demand and Supply
    1. Introduction to Demand and Supply
    2. 3.1 Demand, Supply, and Equilibrium in Markets for Goods and Services
    3. 3.2 Shifts in Demand and Supply for Goods and Services
    4. 3.3 Changes in Equilibrium Price and Quantity: The Four-Step Process
    5. 3.4 Price Ceilings and Price Floors
    6. 3.5 Demand, Supply, and Efficiency
    7. Key Terms
    8. Key Concepts and Summary
    9. Self-Check Questions
    10. Review Questions
    11. Critical Thinking Questions
    12. Problems
  5. 4 Labor and Financial Markets
    1. Introduction to Labor and Financial Markets
    2. 4.1 Demand and Supply at Work in Labor Markets
    3. 4.2 Demand and Supply in Financial Markets
    4. 4.3 The Market System as an Efficient Mechanism for Information
    5. Key Terms
    6. Key Concepts and Summary
    7. Self-Check Questions
    8. Review Questions
    9. Critical Thinking Questions
    10. Problems
  6. 5 Elasticity
    1. Introduction to Elasticity
    2. 5.1 Price Elasticity of Demand and Price Elasticity of Supply
    3. 5.2 Polar Cases of Elasticity and Constant Elasticity
    4. 5.3 Elasticity and Pricing
    5. 5.4 Elasticity in Areas Other Than Price
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  7. 6 The Macroeconomic Perspective
    1. Introduction to the Macroeconomic Perspective
    2. 6.1 Measuring the Size of the Economy: Gross Domestic Product
    3. 6.2 Adjusting Nominal Values to Real Values
    4. 6.3 Tracking Real GDP over Time
    5. 6.4 Comparing GDP among Countries
    6. 6.5 How Well GDP Measures the Well-Being of Society
    7. Key Terms
    8. Key Concepts and Summary
    9. Self-Check Questions
    10. Review Questions
    11. Critical Thinking Questions
    12. Problems
  8. 7 Economic Growth
    1. Introduction to Economic Growth
    2. 7.1 The Relatively Recent Arrival of Economic Growth
    3. 7.2 Labor Productivity and Economic Growth
    4. 7.3 Components of Economic Growth
    5. 7.4 Economic Convergence
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  9. 8 Unemployment
    1. Introduction to Unemployment
    2. 8.1 How Economists Define and Compute Unemployment Rate
    3. 8.2 Patterns of Unemployment
    4. 8.3 What Causes Changes in Unemployment over the Short Run
    5. 8.4 What Causes Changes in Unemployment over the Long Run
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  10. 9 Inflation
    1. Introduction to Inflation
    2. 9.1 Tracking Inflation
    3. 9.2 How to Measure Changes in the Cost of Living
    4. 9.3 How the U.S. and Other Countries Experience Inflation
    5. 9.4 The Confusion Over Inflation
    6. 9.5 Indexing and Its Limitations
    7. Key Terms
    8. Key Concepts and Summary
    9. Self-Check Questions
    10. Review Questions
    11. Critical Thinking Questions
    12. Problems
  11. 10 The International Trade and Capital Flows
    1. Introduction to the International Trade and Capital Flows
    2. 10.1 Measuring Trade Balances
    3. 10.2 Trade Balances in Historical and International Context
    4. 10.3 Trade Balances and Flows of Financial Capital
    5. 10.4 The National Saving and Investment Identity
    6. 10.5 The Pros and Cons of Trade Deficits and Surpluses
    7. 10.6 The Difference between Level of Trade and the Trade Balance
    8. Key Terms
    9. Key Concepts and Summary
    10. Self-Check Questions
    11. Review Questions
    12. Critical Thinking Questions
    13. Problems
  12. 11 The Aggregate Demand/Aggregate Supply Model
    1. Introduction to the Aggregate Supply–Aggregate Demand Model
    2. 11.1 Macroeconomic Perspectives on Demand and Supply
    3. 11.2 Building a Model of Aggregate Demand and Aggregate Supply
    4. 11.3 Shifts in Aggregate Supply
    5. 11.4 Shifts in Aggregate Demand
    6. 11.5 How the AD/AS Model Incorporates Growth, Unemployment, and Inflation
    7. 11.6 Keynes’ Law and Say’s Law in the AD/AS Model
    8. Key Terms
    9. Key Concepts and Summary
    10. Self-Check Questions
    11. Review Questions
    12. Critical Thinking Questions
    13. Problems
  13. 12 The Keynesian Perspective
    1. Introduction to the Keynesian Perspective
    2. 12.1 Aggregate Demand in Keynesian Analysis
    3. 12.2 The Building Blocks of Keynesian Analysis
    4. 12.3 The Phillips Curve
    5. 12.4 The Keynesian Perspective on Market Forces
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
  14. 13 The Neoclassical Perspective
    1. Introduction to the Neoclassical Perspective
    2. 13.1 The Building Blocks of Neoclassical Analysis
    3. 13.2 The Policy Implications of the Neoclassical Perspective
    4. 13.3 Balancing Keynesian and Neoclassical Models
    5. Key Terms
    6. Key Concepts and Summary
    7. Self-Check Questions
    8. Review Questions
    9. Critical Thinking Questions
    10. Problems
  15. 14 Money and Banking
    1. Introduction to Money and Banking
    2. 14.1 Defining Money by Its Functions
    3. 14.2 Measuring Money: Currency, M1, and M2
    4. 14.3 The Role of Banks
    5. 14.4 How Banks Create Money
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  16. 15 Monetary Policy and Bank Regulation
    1. Introduction to Monetary Policy and Bank Regulation
    2. 15.1 The Federal Reserve Banking System and Central Banks
    3. 15.2 Bank Regulation
    4. 15.3 How a Central Bank Executes Monetary Policy
    5. 15.4 Monetary Policy and Economic Outcomes
    6. 15.5 Pitfalls for Monetary Policy
    7. Key Terms
    8. Key Concepts and Summary
    9. Self-Check Questions
    10. Review Questions
    11. Critical Thinking Questions
    12. Problems
  17. 16 Exchange Rates and International Capital Flows
    1. Introduction to Exchange Rates and International Capital Flows
    2. 16.1 How the Foreign Exchange Market Works
    3. 16.2 Demand and Supply Shifts in Foreign Exchange Markets
    4. 16.3 Macroeconomic Effects of Exchange Rates
    5. 16.4 Exchange Rate Policies
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  18. 17 Government Budgets and Fiscal Policy
    1. Introduction to Government Budgets and Fiscal Policy
    2. 17.1 Government Spending
    3. 17.2 Taxation
    4. 17.3 Federal Deficits and the National Debt
    5. 17.4 Using Fiscal Policy to Fight Recession, Unemployment, and Inflation
    6. 17.5 Automatic Stabilizers
    7. 17.6 Practical Problems with Discretionary Fiscal Policy
    8. 17.7 The Question of a Balanced Budget
    9. Key Terms
    10. Key Concepts and Summary
    11. Self-Check Questions
    12. Review Questions
    13. Critical Thinking Questions
    14. Problems
  19. 18 The Impacts of Government Borrowing
    1. Introduction to the Impacts of Government Borrowing
    2. 18.1 How Government Borrowing Affects Investment and the Trade Balance
    3. 18.2 Fiscal Policy and the Trade Balance
    4. 18.3 How Government Borrowing Affects Private Saving
    5. 18.4 Fiscal Policy, Investment, and Economic Growth
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  20. 19 Macroeconomic Policy Around the World
    1. Introduction to Macroeconomic Policy around the World
    2. 19.1 The Diversity of Countries and Economies across the World
    3. 19.2 Improving Countries’ Standards of Living
    4. 19.3 Causes of Unemployment around the World
    5. 19.4 Causes of Inflation in Various Countries and Regions
    6. 19.5 Balance of Trade Concerns
    7. Key Terms
    8. Key Concepts and Summary
    9. Self-Check Questions
    10. Review Questions
    11. Critical Thinking Questions
    12. Problems
  21. 20 International Trade
    1. Introduction to International Trade
    2. 20.1 Absolute and Comparative Advantage
    3. 20.2 What Happens When a Country Has an Absolute Advantage in All Goods
    4. 20.3 Intra-industry Trade between Similar Economies
    5. 20.4 The Benefits of Reducing Barriers to International Trade
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  22. 21 Globalization and Protectionism
    1. Introduction to Globalization and Protectionism
    2. 21.1 Protectionism: An Indirect Subsidy from Consumers to Producers
    3. 21.2 International Trade and Its Effects on Jobs, Wages, and Working Conditions
    4. 21.3 Arguments in Support of Restricting Imports
    5. 21.4 How Governments Enact Trade Policy: Globally, Regionally, and Nationally
    6. 21.5 The Tradeoffs of Trade Policy
    7. Key Terms
    8. Key Concepts and Summary
    9. Self-Check Questions
    10. Review Questions
    11. Critical Thinking Questions
    12. Problems
  23. A | The Use of Mathematics in Principles of Economics
  24. B | The Expenditure-Output Model
  25. Answer Key
    1. Chapter 1
    2. Chapter 2
    3. Chapter 3
    4. Chapter 4
    5. Chapter 5
    6. Chapter 6
    7. Chapter 7
    8. Chapter 8
    9. Chapter 9
    10. Chapter 10
    11. Chapter 11
    12. Chapter 12
    13. Chapter 13
    14. Chapter 14
    15. Chapter 15
    16. Chapter 16
    17. Chapter 17
    18. Chapter 18
    19. Chapter 19
    20. Chapter 20
    21. Chapter 21
  26. References
  27. Index
By the end of this section, you will be able to:
  • Explain how productivity growth changes the aggregate supply curve
  • Explain how changes in input prices change the aggregate supply curve

The original equilibrium in the AD/AS diagram will shift to a new equilibrium if the AS or AD curve shifts. When the aggregate supply curve shifts to the right, then at every price level, producers supply a greater quantity of real GDP. When the AS curve shifts to the left, then at every price level, producers supply a lower quantity of real GDP. This module discusses two of the most important factors that can lead to shifts in the AS curve: productivity growth and changes in input prices.

How Productivity Growth Shifts the AS Curve

In the long run, the most important factor shifting the AS curve is productivity growth. Productivity means how much output can be produced with a given quantity of labor. One measure of this is output per worker or GDP per capita. Over time, productivity grows so that the same quantity of labor can produce more output. Historically, the real growth in GDP per capita in an advanced economy like the United States has averaged about 2% to 3% per year, but productivity growth has been faster during certain extended periods like the 1960s and the late 1990s through the early 2000s, or slower during periods like the 1970s. A higher level of productivity shifts the AS curve to the right, because with improved productivity, firms can produce a greater quantity of output at every price level. Figure 11.7 (a) shows an outward shift in productivity over two time periods. The AS curve shifts out from SRAS0 to SRAS1 to SRAS2, and the equilibrium shifts from E0 to E1 to E2. Note that with increased productivity, workers can produce more GDP. Thus, full employment corresponds to a higher level of potential GDP, which we show as a rightward shift in LRAS from LRAS0 to LRAS1 to LRAS2.

The two graphs show how aggregate supply can shift and how these shifts affect points of equilibrium. The graph on the left shows how productivity increases will shift aggregate supply to the right. The graph on the right shows how higher prices for key inputs will shift aggregate supply to the left.
Figure 11.7 Shifts in Aggregate Supply (a) The rise in productivity causes the SRAS curve to shift to the right. The original equilibrium E0 is at the intersection of AD and SRAS0. When SRAS shifts right, then the new equilibrium E1 is at the intersection of AD and SRAS1, and then yet another equilibrium, E2, is at the intersection of AD and SRAS2. Shifts in SRAS to the right, lead to a greater level of output and to downward pressure on the price level. (b) A higher price for inputs means that at any given price level for outputs, a lower real GDP will be produced so aggregate supply will shift to the left from SRAS0 to SRAS1. The new equilibrium, E1, has a reduced quantity of output and a higher price level than the original equilibrium (E0).

A shift in the SRAS curve to the right will result in a greater real GDP and downward pressure on the price level, if aggregate demand remains unchanged. However, if this shift in SRAS results from gains in productivity growth, which we typically measure in terms of a few percentage points per year, the effect will be relatively small over a few months or even a couple of years. Recall how in Choice in a World of Scarcity, we said that a nation's production possibilities frontier is fixed in the short run, but shifts out in the long run? This is the same phenomenon using a different model.

How Changes in Input Prices Shift the AS Curve

Higher prices for inputs that are widely used across the entire economy can have a macroeconomic impact on aggregate supply. Examples of such widely used inputs include labor and energy products. Increases in the price of such inputs will cause the SRAS curve to shift to the left, which means that at each given price level for outputs, a higher price for inputs will discourage production because it will reduce the possibilities for earning profits. Figure 11.7 (b) shows the aggregate supply curve shifting to the left, from SRAS0 to SRAS1, causing the equilibrium to move from E0 to E1. The movement from the original equilibrium of E0 to the new equilibrium of E1 will bring a nasty set of effects: reduced GDP or recession, higher unemployment because the economy is now further away from potential GDP, and an inflationary higher price level as well. For example, the U.S. economy experienced recessions in 1974–1975, 1980–1982, 1990–91, 2001, and 2007–2009 that were each preceded or accompanied by a rise in the key input of oil prices. In the 1970s, this pattern of a shift to the left in SRAS leading to a stagnant economy with high unemployment and inflation was nicknamed stagflation.

Conversely, a decline in the price of a key input like oil will shift the SRAS curve to the right, providing an incentive for more to be produced at every given price level for outputs. From 1985 to 1986, for example, the average price of crude oil fell by almost half, from $24 a barrel to $12 a barrel. Similarly, from 1997 to 1998, the price of a barrel of crude oil dropped from $17 per barrel to $11 per barrel. In both cases, the plummeting oil price led to a situation like that which we presented earlier in Figure 11.7 (a), where the outward shift of SRAS to the right allowed the economy to expand, unemployment to fall, and inflation to decline.

Along with energy prices, two other key inputs that may shift the SRAS curve are the cost of labor, or wages, and the cost of imported goods that we use as inputs for other products. In these cases as well, the lesson is that lower prices for inputs cause SRAS to shift to the right, while higher prices cause it to shift back to the left. Note that, unlike changes in productivity, changes in input prices do not generally cause LRAS to shift, only SRAS.

Other Supply Shocks

The aggregate supply curve can also shift due to shocks to input goods or labor. For example, an unexpected early freeze could destroy a large number of agricultural crops, a shock that would shift the AS curve to the left since there would be fewer agricultural products available at any given price.

Similarly, shocks to the labor market can affect aggregate supply. An extreme example might be an overseas war that required a large number of workers to cease their ordinary production in order to go fight for their country. In this case, SRAS and LRAS would both shift to the left because there would be fewer workers available to produce goods at any given price.

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