Macroeconomics Study Notes: Economic Growth, Financial System, Money, Monetary Policy, and Open Economy

Economic Growth, the Financial System, and Business Cycles

Business Cycles vs. Long-Run Economic Growth

• Business cycles refer to short-term fluctuations in economic activity, typically caused by specific shocks (e.g., oil price changes, financial crises).

• Long-run economic growth involves sustained increases in productivity and output over several years, leading to higher living standards.

Growth Rate Calculations

• The growth rate of real GDP is the percentage change in real GDP from the previous year.

• Formula: $\text{Growth Rate} = \frac{\text{Real GDP}_{t} - \text{Real GDP}_{t-1}}{\text{Real GDP}_{t-1}} \times 100$

Rule of 70

• The Rule of 70 estimates the number of years it takes for a variable (such as real GDP per capita) to double, given a constant growth rate.

• Formula: $\text{Number of years to double} = \frac{70}{\text{Growth Rate}}$

• Example: If the growth rate is 2%, it will take approximately 35 years for GDP to double.

Productivity

• Definition: The quantity of goods and services produced by one worker or one hour of work.

• Key to economic growth: Higher productivity leads to increased output and income.

• Determinants:

  • Human Capital: Knowledge and skills acquired by workers.

  • Physical Capital: Machinery, tools, and infrastructure.

  • Natural Resources: Inputs from nature (land, minerals, etc.).

  • Technology: Methods and processes for transforming inputs into outputs.

• Difference between human capital and technology: Human capital refers to the skills and knowledge of workers, while technology refers to the processes and innovations used in production.

Productivity and National Income

• Higher productivity growth increases economic output, leading to higher national income and living standards.

Actual and Potential GDP

• Actual GDP: The real output currently produced by the economy.

• Potential GDP: The level of real GDP the economy can produce when operating at full employment.

Savings and Investment

• National savings: Total saving in the economy available for investment.

• Formula: $\text{National Savings} = (Y - T - C) + (T - G)$

• Private savings: Saving by households out of disposable income. $\text{Private Savings} = Y - T - C$

• Budget deficit: When government spending exceeds tax revenue.

• Budget surplus: When tax revenue exceeds government spending.

• Savings-Investment Identity (Closed Economy): $S = I$ (Savings equals Investment)

Loanable Funds Model

• Explains how the market interest rate is determined by the supply and demand for loanable funds.

• Public policies and the loanable funds market:

  • Saving incentives: (e.g., lower taxes on interest income) increase the supply of loanable funds, lowering real interest rates and increasing investment.

  • Investment incentives: (e.g., tax credits for investment) increase the demand for loanable funds, raising real interest rates and investment.

  • Budget deficit: Increases demand for loanable funds, raising interest rates.

  • Budget surplus: Increases supply of loanable funds, lowering interest rates.

Long-Run Economic Growth: Sources and Policies

Role of Public Policy in Economic Growth

• Public policy can influence economic growth by affecting investment, taxation, human capital development, public goods and infrastructure, and regulatory frameworks.

Economic Growth and Living Standards

• Economic growth increases income, employment, and access to goods and services.

• The benefits of growth depend on distribution and public policy.

Productivity and Economic Growth

• Productivity growth is essential for long-run economic growth, higher living standards, and increased output and income.

Diminishing Returns to Capital

• As capital per worker increases, output rises, but each additional unit of capital yields smaller increases in output.

• Solow Growth Model: Focuses on the roles of technological change and capital accumulation in economic growth.

Technology and Productivity Growth

• Technological progress transforms industries, improves efficiency, creates new markets, and is essential for sustained growth.

• Low productivity growth leads to low GDP growth.

New Growth Model (Paul Romer)

• Emphasizes that technological change is driven by economic incentives and the workings of the market system.

Catch-Up Effect

• Poor countries tend to grow faster than rich countries because they have less capital per worker and can adopt existing technologies.

Public Policies and the Loanable Funds Model

• Similar to the discussion in Chapter 10, public policies can shift the supply and demand for loanable funds, affecting interest rates and investment.

Banks, Money, and the Federal Reserve System

Definition and Functions of Money

• Money is any asset that people are generally willing to accept in exchange for goods and services or for payment of debts.

• Functions of money:

  1. Medium of exchange

  2. Unit of account

  3. Store of value

  4. Standard of deferred payment

Types of Money

• Commodity money: Has intrinsic value (e.g., gold, silver).

• Fiat money: Has value because the government declares it legal tender (e.g., paper currency).

Money Supply: M1 and M2

• M1: Currency in circulation, checking account deposits, and savings account deposits.

• M2: M1 plus small-denomination time deposits and non-institutional money market fund shares.

Financial System: Commercial and Central Banks

• Commercial banks: Accept deposits and make loans.

• Central banks: Manage monetary policy, ensure financial stability, and promote economic growth (e.g., Federal Reserve in the US).

Fractional Reserve Banking System

• Banks keep only a fraction of deposits as reserves; the rest is loaned out.

• Required reserves: Minimum reserves banks must hold by law.

• Excess reserves: Reserves held above the required minimum.

Money Creation, Money Multiplier, Reserve Ratio

• Money multiplier: The amount of money the banking system generates with each dollar of reserves.

• Formula: $\text{Money Multiplier} = \frac{1}{\text{Reserve Ratio}}$

• Inverse relationship: As the reserve ratio increases, the money multiplier decreases.

Bank Balance Sheets

• Assets: Loans, reserves, securities.

• Liabilities: Deposits, borrowings.

Role of the Central Bank (Federal Reserve)

• Manages monetary policy, regulates banks, and acts as lender of last resort.

Monetary Policy Tools

• Open market operations, discount rate, reserve requirements.

• Federal Funds Rate: The interest rate at which banks lend reserves to each other overnight.

Money Growth and Inflation

• In the long run, increases in the money supply lead to higher prices (inflation).

Quantity Theory of Money

• Links money supply growth to inflation.

• Equation: $M \times V = P \times Y$ Where $M$ = money supply, $V$ = velocity of money, $P$ = price level, $Y$ = real output.

Monetary Neutrality and Classical Dichotomy

• Monetary neutrality: Changes in the money supply affect only nominal variables, not real variables.

• Classical dichotomy: Real variables (output, employment) are independent of nominal variables (money supply, prices).

Real and Nominal Variables

• Real variables: Adjusted for inflation (e.g., real GDP, real interest rates).

• Nominal variables: Measured in current prices (e.g., nominal GDP, nominal interest rates).

Cost of Inflation and Hyperinflation

• Inflation erodes purchasing power and can distort economic decisions.

• Hyperinflation: Extremely high and accelerating inflation, often leading to economic collapse.

Monetary Policy

Goals of Monetary Policy

• Price stability: Keeping inflation low and stable.

• High employment: Achieving low unemployment.

• Stability of financial markets and institutions.

• Economic growth.

Monetary Expansion and Contraction

• Monetary expansion: Central bank increases the money supply, typically lowering interest rates and stimulating investment and consumption.

• Monetary contraction: Central bank decreases the money supply, raising interest rates and slowing economic activity.

• Example: During the 2008 recession, the Fed lowered interest rates to encourage borrowing and investment.

• Lender of last resort: The Fed provides liquidity to banks to prevent collapse.

Monetary Policy and Aggregate Demand/Supply

• Interest rates affect aggregate demand by influencing consumption, investment, and net exports.

• Changes in price levels move the economy along the aggregate demand curve.

Inflation, Unemployment, and Federal Reserve Policy

Short-Run Trade-off: Phillips Curve

• The short-run Phillips curve shows an inverse relationship between inflation and unemployment.

• Higher inflation is associated with lower unemployment, and vice versa.

• Disinflation: A significant reduction in the inflation rate.

Short-Run and Long-Run Phillips Curves

• The long-run Phillips curve is vertical, indicating no trade-off between inflation and unemployment in the long run.

• The short-run Phillips curve can shift due to changes in aggregate demand or supply.

AD-AS Model and the Phillips Curve

• Aggregate demand and supply curves help explain movements along and shifts of the Phillips curve.

Monetary Policy and Inflation Expectations

• Expectations of inflation influence wage-setting and price-setting behavior.

• Rational expectations: People use all available information to forecast economic variables.

Federal Reserve Policy Since the 1970s

• Example: Oil price shocks in the 1970s shifted the short-run aggregate supply curve left, causing stagflation.

• The Fed sometimes prioritized reducing unemployment over controlling inflation, which could worsen inflation.

Open Economy Macroeconomics

Closed vs. Open Economy

• Open economy: Engages in trade and financial transactions with other countries.

• Closed economy: No international trade or financial flows.

Components of an Open Economy

• Output markets: Trade of goods and services across borders.

• Financial markets: Cross-border movement of capital and investments.

• Labor markets: International mobility of workers.

Net Exports

• Definition: Value of exports minus value of imports.

• Positive net exports contribute to economic growth and higher national income.

• Determinants: Exchange rates, trade policies, and global economic conditions.

Net Capital Outflows

• Definition: Net flow of funds invested abroad by a country.

• Positive net capital outflow indicates more investment abroad than received from foreigners.

• Impacts currency value, interest rates, and economic health.

Savings-Investment Identity (Open Economy)

• In an open economy: $S = I + NCO$ Where $S$ = national savings, $I$ = domestic investment, $NCO$ = net capital outflow.

Exchange Rates

• Nominal exchange rate: Value of one currency in terms of another.

• Real exchange rate: Price of domestic goods in terms of foreign goods.

• Formula: $\text{Real Exchange Rate} = \text{Nominal Exchange Rate} \times \frac{\text{Domestic Price Level}}{\text{Foreign Price Level}}$

Appreciation and Depreciation

• Appreciation: Increase in the value of a currency relative to another; makes exports more expensive and imports cheaper.

• Depreciation: Decrease in the value of a currency; makes exports cheaper and imports more expensive, potentially increasing inflation.