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Principles of Macroeconomics for AP® Courses

17.1 How Government Borrowing Affects Investment and the Trade Balance

Principles of Macroeconomics for AP® Courses17.1 How Government Borrowing Affects Investment and the Trade Balance
  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 Economies Can Be Organized: 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 The Macroeconomic Perspective
    1. Introduction to the Macroeconomic Perspective
    2. 5.1 Measuring the Size of the Economy: Gross Domestic Product
    3. 5.2 Adjusting Nominal Values to Real Values
    4. 5.3 Tracking Real GDP over Time
    5. 5.4 Comparing GDP among Countries
    6. 5.5 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
  7. 6 Economic Growth
    1. Introduction to Economic Growth
    2. 6.1 The Relatively Recent Arrival of Economic Growth
    3. 6.2 Labor Productivity and Economic Growth
    4. 6.3 Components of Economic Growth
    5. 6.4 Economic Convergence
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  8. 7 Unemployment
    1. Introduction to Unemployment
    2. 7.1 How the Unemployment Rate Is Defined and Computed
    3. 7.2 Patterns of Unemployment
    4. 7.3 What Causes Changes in Unemployment over the Short Run
    5. 7.4 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
  9. 8 Inflation
    1. Introduction to Inflation
    2. 8.1 Tracking Inflation
    3. 8.2 How Changes in the Cost of Living Are Measured
    4. 8.3 How the U.S. and Other Countries Experience Inflation
    5. 8.4 The Confusion Over Inflation
    6. 8.5 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
  10. 9 The International Trade and Capital Flows
    1. Introduction to the International Trade and Capital Flows
    2. 9.1 Measuring Trade Balances
    3. 9.2 Trade Balances in Historical and International Context
    4. 9.3 Trade Balances and Flows of Financial Capital
    5. 9.4 The National Saving and Investment Identity
    6. 9.5 The Pros and Cons of Trade Deficits and Surpluses
    7. 9.6 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
  11. 10 The Aggregate Demand/Aggregate Supply Model
    1. Introduction to the Aggregate Demand/Aggregate Supply Model
    2. 10.1 Macroeconomic Perspectives on Demand and Supply
    3. 10.2 Building a Model of Aggregate Demand and Aggregate Supply
    4. 10.3 Shifts in Aggregate Supply
    5. 10.4 Shifts in Aggregate Demand
    6. 10.5 How the AD/AS Model Incorporates Growth, Unemployment, and Inflation
    7. 10.6 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
  12. 11 The Keynesian Perspective
    1. Introduction to the Keynesian Perspective
    2. 11.1 Aggregate Demand in Keynesian Analysis
    3. 11.2 The Building Blocks of Keynesian Analysis
    4. 11.3 The Expenditure-Output (or Keynesian Cross) Model
    5. 11.4 The Phillips Curve
    6. 11.5 The Keynesian Perspective on Market Forces
    7. Key Terms
    8. Key Concepts and Summary
    9. Self-Check Questions
    10. Review Questions
    11. Critical Thinking Questions
  13. 12 The Neoclassical Perspective
    1. Introduction to the Neoclassical Perspective
    2. 12.1 The Building Blocks of Neoclassical Analysis
    3. 12.2 The Policy Implications of the Neoclassical Perspective
    4. 12.3 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
  14. 13 Money and Banking
    1. Introduction to Money and Banking
    2. 13.1 Defining Money by Its Functions
    3. 13.2 Measuring Money: Currency, M1, and M2
    4. 13.3 The Role of Banks
    5. 13.4 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
  15. 14 Monetary Policy and Bank Regulation
    1. Introduction to Monetary Policy and Bank Regulation
    2. 14.1 The Federal Reserve Banking System and Central Banks
    3. 14.2 Bank Regulation
    4. 14.3 How a Central Bank Executes Monetary Policy
    5. 14.4 Monetary Policy and Economic Outcomes
    6. 14.5 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
  16. 15 Exchange Rates and International Capital Flows
    1. Introduction to Exchange Rates and International Capital Flows
    2. 15.1 How the Foreign Exchange Market Works
    3. 15.2 Demand and Supply Shifts in Foreign Exchange Markets
    4. 15.3 Macroeconomic Effects of Exchange Rates
    5. 15.4 Exchange Rate Policies
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  17. 16 Government Budgets and Fiscal Policy
    1. Introduction to Government Budgets and Fiscal Policy
    2. 16.1 Government Spending
    3. 16.2 Taxation
    4. 16.3 Federal Deficits and the National Debt
    5. 16.4 Using Fiscal Policy to Fight Recession, Unemployment, and Inflation
    6. 16.5 Automatic Stabilizers
    7. 16.6 Practical Problems with Discretionary Fiscal Policy
    8. 16.7 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
  18. 17 The Impacts of Government Borrowing
    1. Introduction to the Impacts of Government Borrowing
    2. 17.1 How Government Borrowing Affects Investment and the Trade Balance
    3. 17.2 Fiscal Policy, Investment, and Economic Growth
    4. 17.3 How Government Borrowing Affects Private Saving
    5. 17.4 Fiscal Policy and the Trade Balance
    6. Key Terms
    7. Key Concepts and Summary
    8. Self-Check Questions
    9. Review Questions
    10. Critical Thinking Questions
    11. Problems
  19. 18 Macroeconomic Policy Around the World
    1. Introduction to Macroeconomic Policy around the World
    2. 18.1 The Diversity of Countries and Economies across the World
    3. 18.2 Improving Countries’ Standards of Living
    4. 18.3 Causes of Unemployment around the World
    5. 18.4 Causes of Inflation in Various Countries and Regions
    6. 18.5 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
  20. A | The Use of Mathematics in Principles of Economics
  21. B | Indifference Curves
  22. C | Present Discounted Value
  23. 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
  24. References
  25. Index

By the end of this section, you will be able to:

  • Explain the national saving and investment identity in terms of demand and supply
  • Evaluate the role of budget surpluses and trade surpluses in national saving and investment identity

When governments are borrowers in financial markets, there are three possible sources for the funds from a macroeconomic point of view: (1) households might save more; (2) private firms might borrow less; and (3) the additional funds for government borrowing might come from outside the country, from foreign financial investors. Let’s begin with a review of why one of these three options must occur, and then explore how interest rates and exchange rates adjust to these connections.

The National Saving and Investment Identity

The national saving and investment identity, first introduced in The International Trade and Capital Flows chapter, provides a framework for showing the relationships between the sources of demand and supply in financial capital markets. The identity begins with a statement that must always hold true: the quantity of financial capital supplied in the market must equal the quantity of financial capital demanded.

The U.S. economy has two main sources for financial capital: private savings from inside the U.S. economy and public savings.

Total savings = Private savings (S) + Public savings (T – G)Total savings = Private savings (S) + Public savings (T – G)

These include the inflow of foreign financial capital from abroad. The inflow of savings from abroad is, by definition, equal to the trade deficit, as explained in The International Trade and Capital Flows chapter. So this inflow of foreign investment capital can be written as imports (M) minus exports (X). There are also two main sources of demand for financial capital: private sector investment (I) and government borrowing. Government borrowing in any given year is equal to the budget deficit, and can be written as the difference between government spending (G) and net taxes (T). Let’s call this equation 1.

Quantity supplied of financial capital = Quantity demanded of financial capitalPrivate savings + Inflow of foreign savings = Private investment + Government budget deficitS + (M – X) = I + (G –T)Quantity supplied of financial capital = Quantity demanded of financial capitalPrivate savings + Inflow of foreign savings = Private investment + Government budget deficitS + (M – X) = I + (G –T)

Governments often spend more than they receive in taxes and, therefore, public savings (T – G) is negative. This causes a need to borrow money in the amount of (G – T) instead of adding to the nation’s savings. If this is the case, governments can be viewed as demanders of financial capital instead of suppliers. So, in algebraic terms, the national savings and investment identity can be rewritten like this:

Private investment = Private savings + Public savings + Trade deficitI = S + (T – G) + (M – X)Private investment = Private savings + Public savings + Trade deficitI = S + (T – G) + (M – X)

Let’s call this equation 2. A change in any part of the national saving and investment identity must be accompanied by offsetting changes in at least one other part of the equation because the equality of quantity supplied and quantity demanded is always assumed to hold. If the government budget deficit changes, then either private saving or investment or the trade balance—or some combination of the three—must change as well. Figure 17.2 shows the possible effects.

Following from the national savings and investment identity, charts (a) and (b) show what happens to investment, private savings, and the trade deficit when the budget deficit rises (or the budget surplus falls). (a) If the budget deficit rises (or the government budget surplus falls), the results could be (1) domestic private investment falls or (2) private savings rise or (3) the trade deficit increases (or a trade surplus diminishes). The opposite results of each are achieved when the budget deficit falls (or the budget surplus rises) as shown in image (b).
Figure 17.2 Effects of Change in Budget Surplus or Deficit on Investment, Savings, and The Trade Balance Chart (a) shows the potential results when the budget deficit rises (or budget surplus falls). Chart (b) shows the potential results when the budget deficit falls (or budget surplus rises).

What about Budget Surpluses and Trade Surpluses?

The national saving and investment identity must always hold true because, by definition, the quantity supplied and quantity demanded in the financial capital market must always be equal. However, the formula will look somewhat different if the government budget is in deficit rather than surplus or if the balance of trade is in surplus rather than deficit. For example, in 1999 and 2000, the U.S. government had budget surpluses, although the economy was still experiencing trade deficits. When the government was running budget surpluses, it was acting as a saver rather than a borrower, and supplying rather than demanding financial capital. As a result, the national saving and investment identity during this time would be more properly written:

Quantity supplied of financial capital =Quantity demanded of financial capital Private savings + Trade deficit + Government surplus= Private investment S + (M – X) + (T – G) = IQuantity supplied of financial capital =Quantity demanded of financial capital Private savings + Trade deficit + Government surplus= Private investment S + (M – X) + (T – G) = I

Let's call this equation 3. Notice that this expression is mathematically the same as equation 2 except the savings and investment sides of the identity have simply flipped sides.

During the 1960s, the U.S. government was often running a budget deficit, but the economy was typically running trade surpluses. Since a trade surplus means that an economy is experiencing a net outflow of financial capital, the national saving and investment identity would be written:

Quantity supplied of financial capital=Quantity demanded of financial capitalPrivate savings=Private investment + Outflow of foreign savings + Government budget deficitS=I + (X – M) + (G – T)Quantity supplied of financial capital=Quantity demanded of financial capitalPrivate savings=Private investment + Outflow of foreign savings + Government budget deficitS=I + (X – M) + (G – T)

Instead of the balance of trade representing part of the supply of financial capital, which occurs with a trade deficit, a trade surplus represents an outflow of financial capital leaving the domestic economy and being invested elsewhere in the world.

Quantity supplied of financial capital=Quantity demanded of financial capital demandPrivate savings=Private investment + Government budget deficit + Trade surplusS=I + (G – T) + (X – M) Quantity supplied of financial capital=Quantity demanded of financial capital demandPrivate savings=Private investment + Government budget deficit + Trade surplusS=I + (G – T) + (X – M) 

The point to this parade of equations is that the national saving and investment identity is assumed to always hold. So when you write these relationships, it is important to engage your brain and think about what is on the supply side and what is on the demand side of the financial capital market before you put pencil to paper.

As can be seen in Figure 17.3, the Office of Management and Budget shows that the United States has consistently run budget deficits since 1977, with the exception of 1999 and 2000. What is alarming is the dramatic increase in budget deficits that has occurred since 2008, which in part reflects declining tax revenues and increased safety net expenditures due to the Great Recession. (Recall that T is net taxes. When the government must transfer funds back to individuals for safety net expenditures like Social Security and unemployment benefits, budget deficits rise.) These deficits have implications for the future health of the U.S. economy.

The graph shows U.S. government budgets and surpluses from 1977 to 2014. The United States has only had two years without a government budget deficit. In the 1980s the deficit hovered above –$200 million, gradually becoming a surplus by the end of 1990s. From 2000 onward, the deficit grew rapidly to –$600 million. The deficit was at its worst in 2009, at close to $1.6 trillion, following the Great Recession. In 2014, it was around –$514 million.
Figure 17.3 United States On-Budget, Surplus, and Deficit, 1977–2014 ($ millions) The United States has run a budget deficit for over 30 years, with the exception of 1999 and 2000. Military expenditures, entitlement programs, and the decrease in tax revenue coupled with increased safety net support during the Great Recession are major contributors to the dramatic increases in the deficit after 2008. (Source: Table 1.1, "Summary of Receipts, Outlays, and Surpluses or Deficits," https://www.whitehouse.gov/omb/budget/Historicals)

A rising budget deficit may result in a fall in domestic investment, a rise in private savings, or a rise in the trade deficit. The following modules discuss each of these possible effects in more detail.

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