lecture 9: Business Cycles and Quantity Theory of Money

Emphasis on analyzing deviations from the long run trend rather than the trend itself, allowing for a clearer understanding of the factors influencing economic fluctuations.

Real GDP shows fluctuations from 1947 to 2009, with long-term growth trends evident.
HP-Filtered Trend: This statistical method helps to identify and analyze deviations from the trend, providing insight into periods of recession and expansion by smoothing out short-term fluctuations.

Key Features of Recessions and Expansions:
- Volatility: This represents the degree of fluctuations in economic activity, which can indicate the stability of the economy.
- Co-movement: A concept referring to how economic variables (like GDP, employment, and wages) tend to move together, indicating connections between different sectors.
- Phase Shift: Refers to timing differences in the movements of various economic variables, highlighting the synchronized yet staggered nature of economic cycles.

Average Deviation: The average deviation of GDP from its trend is 1.7%, indicating the typical extent to which the GDP may stray from expected values.
Investment Volatility: Much higher than GDP, with an average deviation of 8%, indicating that investments can be four times more volatile than GDP. This illustrates the sensitivity of capital expenditures to economic conditions.
Consumption Volatility: Much less volatile than GDP, averaging a deviation of 1.3%, showing more consistency in consumer spending patterns than in investment. This stability in consumption underscores its importance as a driver of economic growth.

Expenditures:
- GDP: 1.
- Consumption (C): 0.75 (Pro-cyclical). Consumption tends to increase when the economy grows.
- Investment (I): 4.7 (Pro-cyclical). Investment is highly responsive to economic cycles, increasing during economic expansions.
Labor Inputs:
- Employment: 2/3 (Pro-cyclical, slight lag). Employment often responds to economic changes with a slight delay.
- Hours per worker: 1/3 (Pro-cyclical, neither leads nor lags significantly). Hours worked may fluctuate with economic changes but not in a way that consistently leads or lags behind overall economic performance.

Capital investments, such as factories or machinery, take time to establish, which can delay economic recovery.
Typically, firms increase hours of existing employees before hiring new workers, which usually occurs within a three-month timeframe as demand conditions improve.

Aggregate Data: Real wages do not display a clear pro- or counter-cyclical pattern, indicating stability across economic cycles.
Micro Data: Found to be pro-cyclical due to 'composition bias,' where wages tend to increase as higher productivity accompanies economic growth.

1973-1975: Coinciding with an OPEC oil price increase, leading to a period of stagflation characterized by rising prices and stagnant economic growth.
1980-1982: The period marked by Volcker disinflation, which aimed to curb runaway inflation but resulted in high unemployment.
1990-1991: Economic slowdown attributed to the S&P collapse and rising oil prices, indicating the interconnectedness of financial markets and energy factors.
2001: An economic downturn caused by the internet stock collapse, exacerbating issues already present in the economy.
2007-2009: The sub-prime mortgage crisis and subsequent housing market collapse, which revealed vulnerabilities in financial systems.
2020: The COVID-19 pandemic's impact brought unprecedented economic challenges, affecting production and consumer behavior.

The causes of the Great Depression remain debated among economists, but it is characterized by:-
- A drastic contraction of the money supply, severely impacting liquidity.
- Significant deflation, which distorted price levels and wages.
- A collapse of financial markets, including widespread banking panics that undermined confidence in the economy.

Stabilization Policy: Aimed at eliminating recessions but could also eliminate expansions, making it challenging to observe benefits directly. Policies should ensure sustainable economic growth without unnecessary fluctuations.
Benefits: The advantages of stabilization are most noted if the economy resembles a stabilized trend growth model, where consistent growth patterns can reduce volatility.

Approaches to Analysis:
1. Use models for the short run, such as AS/AD and IS/LM models, to understand immediate economic conditions.
2. Extend growth models to incorporate cycles by acknowledging factors like technology shocks and nominal rigidities.
The analysis will primarily focus on the first approach, utilizing established models to provide clearer insights into business cycles.

Long Run: Characterized by flexible prices and all inputs, while being influenced by capital accumulation and technological advancements.
Short Run: Encompasses fixed capital and technology, allowing only labor to be flexible, which influences how quickly an economy can respond to changes.

Fundamental question: How does the money supply influence the economy in the long run?
The central premise involves the relationship between the quantity of money in circulation and overall economic activity.
Equation of Exchange: MV = PY (Money supply times velocity equals price level times output), serving as a tool for understanding monetary dynamics.

M1: Defined as cash, demand deposits, and readily available liquid assets, representing the most accessible form of money.
M2: Encompasses M1 plus savings accounts and other partially checkable deposits like small time deposits, indicating a broader measurement of money supply.

Inflation is directly correlated with money supply growth rates, demonstrating how money circulation impacts price levels.
Evidence from multiple countries illustrates a strong correlation between inflation rates and money supply growth, emphasizing the importance of managing the monetary base.

Typically defined as an inflation rate exceeding 50% per month, hyperinflation leads to monetary instability and a lack of viable currency options.
Causes: Often results from rapid and excessive money supply growth, especially when governments face significant fiscal pressures, prompting them to print money.
Historical Examples: Documented instances of hyperinflation include notable cases in Zimbabwe and Germany during the interwar period, serving as cautionary tales for economic governance.

Key topics covered included an analysis of business cycle facts and an introduction to the Quantity Theory of Money, emphasizing the role of the money supply in inflation dynamics and overall economic fluctuations.