Comprehensive Study Notes: Money, Banking, Macroeconomic Policy, Growth, and International Trade

Money, Banking, and the Federal Reserve

Fractional Reserve Banking and Money Creation

Modern banks operate under a fractional reserve banking system, where they keep only a fraction of deposits as reserves and lend out the rest. This process is central to money creation in the economy.

• Required Reserves (RR): The minimum fraction of deposits banks must hold, set by the central bank. The required reserve ratio (RRR) is the legal minimum.

• Excess Reserves: Any reserves held above the required minimum.

• Money Multiplier (MM): Indicates how much the money supply increases with each dollar of reserves. $MM = \frac{1}{RRR}$

• Example: If $100 is deposited and RRR = 10\%$, the bank keeps $10 and can lend $90. The process continues as loans are redeposited, expanding the money supply.

Table: Example of Money Creation with RRR = 20\%

Bank	Deposit Received	Reserves Kept	Loan Made
1	$1,000	$200	$800
2	$800	$160	$640
3	$640	$128	$512
...	...	...	...

The Federal Reserve and Interest Rate Control

The Federal Reserve (Fed) manages the money supply and influences interest rates to achieve macroeconomic goals.

• Open Market Operations (OMO): The Fed buys or sells government bonds to adjust bank reserves.

• Buying Bonds: Increases reserves, lowers interest rates, expands money supply (expansionary policy).

• Selling Bonds: Decreases reserves, raises interest rates, contracts money supply (contractionary policy).

• Federal Funds Rate: The overnight interest rate at which banks lend reserves to each other. The Fed targets this rate to influence broader economic activity.

Table: Key U.S. Interest Rates

Rate	Meaning
Federal Funds Rate	Bank-to-bank overnight rate
Prime Rate	Rate banks charge best customers
Mortgage Rate	Home loan interest rate
Treasury Yield	Government borrowing rate

Monetary Policy

• Expansionary Policy: Used during recessions; lowers interest rates and increases money supply to boost aggregate demand (AD), output, and employment.

• Contractionary Policy: Used to combat inflation; raises interest rates and reduces money supply to decrease AD and slow the economy.

Transmission Mechanism:

• ↓ Interest rates → ↑ Borrowing → ↑ Investment → ↑ AD → ↑ Output/Employment

Aggregate Supply and Demand (AS/AD)

Aggregate Demand (AD)

Aggregate Demand is the total quantity of goods and services demanded at different price levels.

• Downward sloping due to the wealth effect (higher prices reduce real wealth), interest rate effect (higher prices raise interest rates, reducing investment), and net export effect (higher prices make exports less competitive).

• Formula: $AD = C + I + G + (X - M)$ Where C = consumption, I = investment, G = government spending, X = exports, M = imports.

Aggregate Supply (AS)

• Short-Run Aggregate Supply (SRAS): Upward sloping due to sticky wages and prices.

• Long-Run Aggregate Supply (LRAS): Vertical at potential GDP; determined by resources and technology, not price level.

Shifts in AS:

Increase SRAS	Decrease SRAS
Lower wages, lower input costs, better productivity	Higher wages, oil shocks, supply disruptions

Equilibrium and Gaps

• Final Equilibrium: Where AD and AS intersect.

• Recessionary Gap: Output below potential, high unemployment.

• Inflationary Gap: Output above potential, inflationary pressure.

Stagflation: Combination of inflation, recession, and unemployment, often caused by negative supply shocks.

Fiscal Policy and Government Debt

Fiscal Policy

Fiscal policy refers to government decisions on spending and taxation to influence the economy.

• Expansionary: Increase spending or decrease taxes to fight recession (increase AD).

• Contractionary: Decrease spending or increase taxes to fight inflation (decrease AD).

• Multiplier Effect: Initial government spending leads to a larger total increase in output.

Government Deficit and Debt

• Deficit: When government spending exceeds tax revenue in a given year.

• Debt: The accumulation of past deficits.

• Crowding Out: Government borrowing raises interest rates, reducing private investment.

Unemployment and Inflation

Types of Unemployment

Type	Cause
Frictional	Job transitions
Structural	Skill mismatch
Cyclical	Recession (lack of AD)

• Natural Rate of Unemployment: The sum of frictional and structural unemployment; the rate when the economy is at potential GDP.

Phillips Curve

• Short-Run Phillips Curve: Inverse relationship between inflation and unemployment.

• Long-Run Phillips Curve: Vertical; no trade-off between inflation and unemployment in the long run.

Inflation Concepts

• Disinflation: A reduction in the rate of inflation (prices rise more slowly).

• Deflation: A decrease in the general price level (prices fall).

• Sacrifice Ratio: The percentage of GDP lost to reduce inflation by 1%.

Economic Growth

Measuring Economic Growth

• Real GDP: Value of all final goods and services produced, adjusted for inflation.

• Real GDP per capita: Real GDP divided by population; indicator of living standards.

• Potential GDP: Output at full employment.

• Rule of 70: Estimates years to double a variable at a given growth rate. $\text{Years to double} = \frac{70}{\text{Growth Rate (\%)}}$

Sources of Economic Growth

• Increase in labor supply

• Increase in physical capital (machines, factories)

• Human capital (education, skills)

• Technological change

• Institutions (property rights, stability)

Production Function: Shows output as a function of inputs (capital, labor, technology). Diminishing Returns: Adding more of one input, holding others constant, yields smaller increases in output.

Theories of Growth

• Classical Growth Theory: Predicts diminishing returns and lower living standards as population grows.

• New Growth Theory: Emphasizes technology and innovation as drivers of sustained growth.

International Trade and Finance

Comparative and Absolute Advantage

• Comparative Advantage: Ability to produce a good at a lower opportunity cost than another producer.

• Absolute Advantage: Ability to produce more efficiently (using fewer resources).

• Countries should specialize in goods where they have comparative advantage and trade for others.

Trade Balances and Barriers

• Trade Surplus: Exports > Imports

• Trade Deficit: Imports > Exports

• Tariff: Tax on imports; raises prices, protects domestic firms, reduces imports.

• Quota: Physical limit on imports; reduces imports, can create deadweight loss.

• Export Subsidy: Government payment to encourage exports.

Balance of Payments and Open Economy

• Balance of Payments: Record of all economic transactions between residents and the rest of the world.

• Current Account: Exports and imports of goods/services, income from abroad, current transfers.

• Financial Account: Transactions involving financial assets and liabilities (e.g., foreign direct investment).

• Open Economy Equilibrium: $AD = C + I + G + (X - M)$

• Currency Effects: Stronger currency makes imports cheaper, exports more expensive; weaker currency does the opposite.

Financial Markets and Crises

Financial Markets and Loanable Funds

• Direct Access: Investors buy stocks, bonds directly.

• Indirect Access: Financial intermediaries (banks, mutual funds) channel savings to borrowers.

• Market for Loanable Funds: Where savers supply funds and borrowers demand them; interest rate balances supply and demand.

• Crowding Out: Government borrowing raises interest rates, reducing private investment.

Financial Crises

• Wealth Effect: Rising asset prices (stocks, housing) make households feel richer, increasing consumption and shifting AD right.

• Financial Crisis: Often caused by asset prices rising above intrinsic value, leading to corrections and reduced lending/investment.

Key Macroeconomic Formulas and Concepts

• Quantity Theory of Money: $MV = PY$ Where M = money supply, V = velocity, P = price level, Y = real output.

• Money Multiplier: $MM = \frac{1}{RRR}$

• Aggregate Demand: $AD = C + I + G + (X - M)$

• Rule of 70: $\text{Years to double} = \frac{70}{\text{Growth Rate (\%)}}$

Additional Info

• Liquidity: How easily an asset can be converted to cash.

• Fiat Money: Money with value by government decree (e.g., U.S. dollar).

• Commodity Money: Money with intrinsic value (e.g., gold).

• M1: Currency, checking deposits, traveler's checks.

• M2: M1 plus savings deposits, small time deposits, money market funds.

• Recognition Lag: Time it takes to identify a recession has begun (fiscal policy lag).

• Taylor Rule: Formula for setting the Federal Funds Rate based on inflation and output gaps.