Macroeconomics Chapter 10: Economic Growth, Financial System, and Business Cycles

Long-Run Economic Growth

Definition and Importance

Long-run economic growth refers to the sustained increase in a nation's output of goods and services over time, typically measured by rising productivity and improvements in the average standard of living.

• Long-run economic growth is the process by which rising productivity increases the average standard of living.

• This is distinct from short-run economic fluctuations, which are inherent to the business cycle—the alternating periods of economic expansion and recession.

• The most commonly used measure of average standard of living is real GDP per capita: the amount of production in the economy, per person, adjusted for changes in the price level.

Growth in Real GDP per Capita

Real GDP per capita has risen more than nine-fold since 1900 in the United States, indicating a significant increase in the ability of the average American to purchase goods and services.

• Example: The average American can buy more than nine times as many goods and services now as in 1900.

Economic Prosperity and Health

Economic prosperity and health are closely linked. Richer nations can devote more resources to improving health, and healthier citizens are more productive.

• Growth in real GDP per capita is an important measure of improvement, but another key measure is the increase in lifespans.

• Life expectancy has increased steadily over the last century in developed nations.

Leisure and Productivity

As productivity grows, people can spend more time on leisure. Higher productivity allows for more time devoted to non-work activities, improving overall well-being.

• As lifespans grow, individuals can allocate more time to leisure.

• Increased productivity means less time is needed for work to achieve the same output.

Calculating Growth Rates

The growth rate of an economic variable, such as real GDP or real GDP per capita, is the percentage change from one year to the next.

• Formula: $\text{Growth Rate} = \frac{\text{Current Year Value} - \text{Previous Year Value}}{\text{Previous Year Value}} \times 100$

• Example: If real GDP was $21.4$ trillion in 2021 and $21.8$ trillion in 2022, the growth rate is $\frac{21.8 - 21.4}{21.4} \times 100 = 1.9\%$

Average Growth Rates Over Multiple Years

For short periods, the average annual growth rate can be calculated by averaging yearly growth rates.

• Example: If growth rates are -2.2%, 5.8%, and 1.9% over three years, the average annual growth rate is $\frac{-2.2 + 5.8 + 1.9}{3} = 1.8\%$

Growth Rates Over Longer Periods

For longer periods, use the formula:

• $\text{Current Real GDP} = \text{Previous Real GDP} \times (1+g)^n$

• Where $g$ is the growth rate and $n$ is the number of periods.

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

• Example: At a 5% growth rate, a variable will double in $\frac{70}{5} = 14$ years.

Determinants of Long-Run Growth

Increases in real GDP per capita depend on increases in labor productivity—the quantity of goods and services produced by one worker or one hour of work.

• Labor productivity growth is the main driver of long-run economic growth.

Factors Affecting Labor Productivity Growth

• Increases in capital per hour worked: More physical and human capital makes workers more productive.

• Technological change: Improvements in capital or methods (new technologies) allow workers to produce more in a given time.

• Property rights: Secure property rights and effective legal systems encourage investment and innovation.

Case Study: India’s Economic Growth

India’s rapid economic rise was unexpected. Market-based reforms and reduced central planning since 1991 led to higher growth rates and a doubling of GDP per capita.

• Continued growth requires infrastructure, improved education and health services, and commitment to the rule of law.

• Regulatory reforms and investment in infrastructure are key for sustained growth.

Potential GDP

Potential GDP is the level of real GDP attained when all firms are operating at capacity (normal hours and workforce size).

• Potential GDP rises with labor force expansion, increased capital stock, and new technologies.

• Actual GDP may fall below potential GDP during recessions.

Saving, Investment, and the Financial System

Role of the Financial System

The financial system facilitates long-run economic growth by channeling funds from savers to borrowers, enabling investment in productive capacity.

• Firms finance expansion through retained earnings and external funds from the financial system.

• The financial system consists of financial markets and financial intermediaries.

Financial Markets and Intermediaries

• Financial markets: Where financial securities (stocks, bonds) are bought and sold.

• Financial security: A document stating the terms under which funds pass from buyer to seller.

• Stock: Represents partial ownership in a firm.

• Bond: Promises to repay a fixed amount; essentially a loan from a household to a firm.

• Financial intermediaries: Firms (banks, mutual funds, pension funds, insurance companies) that borrow funds from savers and lend to borrowers.

Services Provided by the Financial System

• Risk sharing: Diversification reduces risk while maintaining expected returns.

• Liquidity: Savers can quickly convert investments into cash.

• Information: Prices of securities reflect beliefs about future returns, guiding funds to productive uses.

Macroeconomics of Savings and Investment

In a closed economy, total saving equals total investment.

• GDP identity: $Y = C + I + G + NX$

• In a closed economy (no net exports): $Y = C + I + G$

• Rearranged: $I = Y - C - G$

Savings

• Private savings: $S_{private} = Y + TR - C - T$

• Public savings: $S_{public} = T - G - TR$

• Total savings: $S = S_{private} + S_{public} = Y - C - G$

Savings Equals Investment

• In equilibrium, $S = I$

• A balanced budget occurs when $S_{public} = 0$; deficits and surpluses are negative and positive values, respectively.

• Government borrowing (selling Treasury bonds) can crowd out private investment.

The Market for Loanable Funds

The market for loanable funds models the interaction of borrowers and lenders, determining the market interest rate and the quantity of funds exchanged.

• Households supply loanable funds; firms demand them for investment.

• Government saving or dissaving affects the supply of funds.

Table: Summary of the Loanable Funds Model

Participants	Action	Effect on Market
Households	Supply funds	Increase supply, lower interest rates
Firms	Demand funds	Increase demand, raise interest rates
Government	Borrow (deficit)	Decrease supply to firms, raise interest rates (crowding out)

Effects of Changes in the Market

• Technological change: Increases profitability of investment, raising demand for loanable funds and the real interest rate.

• Budget deficit: Government borrowing raises interest rates and reduces funds available for private investment (crowding out).

• Magnitude of crowding out: Typically small, as global markets influence interest rates.

The Business Cycle

Definition and Phases

The business cycle refers to the alternating periods of economic expansion and contraction experienced by the economy.

• Expansion: Periods of rising real GDP.

• Recession: Periods of falling real GDP.

• Peaks and troughs: Points where the economy transitions between phases.

Identifying Recessions

• Media often define a recession as two consecutive quarters of declining real GDP.

• The National Bureau of Economic Research (NBER) defines a recession as a significant decline in activity spread across the economy, lasting more than a few months, visible in industrial production, employment, real income, and wholesale-retail trade.

Features of the Business Cycle

• Near the end of an expansion, interest rates and wages rise faster than other prices; firm profits fall.

• As a recession begins, firms decrease investment and households consume less; employment falls.

• Eventually, conditions improve, investment resumes, and employment recovers.

Effect on Inflation

• Inflation rate: Measures the change in the price level from one year to the next.

• During expansions, high demand leads to higher inflation.

• During recessions, low demand leads to lower inflation or deflation.

Effect on Unemployment

• Firms reduce production and lay off workers during recessions.

• Unemployment often continues to rise after the end of a recession.

• Younger workers are typically more affected by recessions.

Predicting Recessions

• Business cycles are not uniform; leading indicators are unreliable.

• Events triggering recessions are hard to predict.

Historical Fluctuations and the Great Moderation

• Fluctuations in real GDP were greater before 1950; business cycles have been milder since the mid-1980s (the Great Moderation).

• Length and severity of recessions have varied; the 2007-2009 recession was unusually severe.

Factors Contributing to Economic Stability

• Increasing importance of services (less affected by recessions than manufacturing).

• Establishment of unemployment insurance and government transfer programs.

• Active government stabilization policies to lengthen expansions and minimize recessions.

• Stability of the financial system is crucial for macroeconomic stability.