Macroeconomic Problems and Policies
AdvancedThe business cycle makes real output fluctuate around its long-run trend, giving rise to inflation, deflation and unemployment; fiscal policy adjusts government spending and taxes while monetary policy adjusts the money supply and interest rates, both working through aggregate demand.
- The business cycle is real GDP fluctuating around its long-run trend, giving rise to inflation, deflation and unemployment
- Real rate ≈ nominal rate minus inflation; inflation redistributes wealth between creditors and debtors
- Quantity theory: with velocity unchanged, money-supply growth translates proportionally into price rises
文體小知識：經濟現象說明文——分析通脹、通縮與失業的成因和代價，並說明財政政策與貨幣政策如何透過總需求穩定經濟。
§Text Passage
1The business cycle is the recurring short-term fluctuation of real GDP around its long-run trend: in booms output runs above trend with firms expanding and unemployment low; in recessions output falls below trend, orders shrink and unemployment rises. The cycle brings two major macro problems: unstable prices and unemployment.
2Inflation is a sustained rise in the general price level; deflation is the opposite. Inflation redistributes wealth: debtors gain while creditors lose, and those on fixed incomes suffer most. The real interest rate roughly equals the nominal rate minus the inflation rate — the higher inflation, the lower the real return at any nominal rate. The quantity theory of money states that, with velocity unchanged, growth in the money supply raises the general price level.
3The unemployed are those in the labour force who are actively seeking work but have none; the unemployment rate is the unemployed as a percentage of the labour force. Unemployment means lost output, skill erosion and social costs; the underemployed are those working but involuntarily working fewer hours than they would like.
4Fiscal policy manages aggregate demand through government spending and taxes: raising spending or cutting taxes in a downturn is expansionary, the reverse is contractionary in an overheating economy; budgets are surplus, deficit or balanced. Monetary policy works through the money supply and interest rates set by the monetary authority: easier money lowers rates and lifts consumption and investment. Both policies shift aggregate demand, but each has lags and limits.
1Summary 重點摘要
The business cycle makes real output fluctuate around its long-run trend, giving rise to inflation, deflation and unemployment; fiscal policy adjusts government spending and taxes while monetary policy adjusts the money supply and interest rates, both working through aggregate demand.
2Vocabulary cards Vocabulary
The recurring short-term fluctuation of real GDP around its long-run trend.
A sustained rise in the general price level; 'general' and 'sustained' are the key words.
A sustained fall in the general price level, usually signalling weak aggregate demand.
The interest rate in money terms, before adjusting for inflation.
The rate measuring the true growth of purchasing power; roughly the nominal rate minus the inflation rate.
Inflation's reallocation of wealth between creditors and debtors, and between fixed- and flexible-income earners.
Money supply times velocity equals the price level times real output; with velocity unchanged, money-supply growth raises prices.
Government policy managing aggregate demand through spending and taxes; expansionary or contractionary.
A budget with revenue above spending is a surplus budget; spending above revenue is a deficit budget; equal amounts make a balanced budget.
Policy by the monetary authority managing aggregate demand through the money supply and interest rates.
3Step by step Steps
- Step 1: The shape of the business cycleThe business cycle is the recurring short-term fluctuation of real GDP around its long-run trend: in booms output is above trend, firms expand and unemployment is low; in recessions output is below trend, orders shrink and unemployment rises. The syllabus only requires describing the fluctuation, not theories of its causes. For example, the pandemic collapse in tourism and retail was a typical recession; the later rebound above trend completed the cycle.
- Step 2: Defining inflation and deflationInflation is a sustained rise in the general price level; deflation is a sustained fall. Two key words: 'general' — a price rise in one good does not count; 'sustained' — a one-off jump does not count. Measurement uses general price indices such as the consumer price index. For example, vegetable prices doubling in a typhoon month and falling back is a temporary movement; if rents, transport and dining all rise for several quarters, that is inflation.
- Step 3: Nominal and real interest ratesThe nominal rate is the stated rate; the real rate measures the true growth of purchasing power and roughly equals the nominal rate minus inflation. The higher inflation, the lower the real return on the same time deposit; when inflation exceeds the nominal rate, the real rate is negative and savers lose purchasing power. For example, at 5% nominal and 2% inflation, deposits grow about 3% in real terms; at 6% inflation the real rate is about −1%.
- Step 4: The redistribution effect of inflationUnexpected inflation reallocates wealth between creditors and debtors, and between fixed- and flexible-income earners: debtors repay in money of lower purchasing power and gain; creditors receive money that buys less and lose; those on fixed salaries and pensions see purchasing power steadily eroded. For example, with 10% inflation a mortgage holder's real burden falls by about a tenth, while bondholders on fixed coupons and pensioners watch their real incomes shrink.
- Step 5: The quantity theory of moneyThe quantity theory is written as an identity: money supply times velocity equals the price level times real output (MV = PQ). With velocity assumed constant, the percentage increase in the money supply translates into the same percentage rise in the general price level — inflation is ultimately a monetary phenomenon. For example, with a 10% rise in money supply and unchanged velocity and output, prices rise 10%; this explains why over-expanding the money supply ends in high inflation.
- Step 6: Measuring unemployment and underemploymentThe unemployed are of working age, without work, available for work and actively seeking it. The unemployment rate equals the unemployed divided by the labour force times 100%, and the labour force is the employed plus the unemployed. The underemployed work but involuntarily work fewer hours than desired. The costs of unemployment include lost output, skill erosion and social problems. For example, a labour force of 3.8 million with 120,000 unemployed gives a rate of about 3.2%; students and retirees are not in the labour force — a common trap.
- Step 7: Fiscal policy and monetary policyFiscal policy is the government managing aggregate demand through spending and taxes: raising public spending or cutting taxes in a downturn is expansionary; cutting spending or raising taxes in an overheating economy is contractionary. Budgets are surplus, deficit or balanced; taxes are direct or indirect, progressive, proportional or regressive. Monetary policy works through money supply and interest rates: easier money lowers rates and lifts consumption and investment. For example, in a recession, more infrastructure spending plus easier money shifts AD right, raising output and employment.
5Worked example Example
Application practice: an economy has a labour force of 3.8 million with 120,000 unemployed; the general price level has fallen for four consecutive quarters; the nominal interest rate is 3%. Calculate the unemployment rate, identify the economy's main problem, recommend a suitable fiscal policy, and explain its effects on output and the price level.
- Unemployment rate: 120,000 ÷ 3,800,000 × 100% ≈ 3.2% — mild, so a deep recession can be ruled out at first glance
- Main problem: four consecutive quarters of falling prices signal deflation and weak aggregate demand; under deflation the real rate exceeds the nominal rate, curbing consumption and investment
- Recommended policy: expansionary fiscal policy — raise public spending (for example infrastructure and healthcare) or cut taxes to boost aggregate demand directly
- Effects: the AD curve shifts right, equilibrium output and employment rise, and the price level stops falling and recovers, helping the economy exit deflation
- Answer: The unemployment rate is about 3.2%, which is mild; the economy's main problem is deflation — weak aggregate demand, with deflation pushing up the real interest rate and restraining spending. An expansionary fiscal policy is recommended: higher public spending or tax cuts shift the AD curve right, raising equilibrium output and employment while the price level recovers, helping the economy out of deflation.
6Common mistakes Mistakes
7Quick check Quick check
Q1How is the real interest rate approximated? With a 5% nominal rate and 2% inflation, what is it?
Q2Under inflation's redistribution effect, how are debtors and creditors affected?
Q3With velocity and output unchanged, what does the quantity theory of money conclude?
Q4With a labour force of 3 million and 150,000 unemployed, what is the unemployment rate?
Q5Which direction of fiscal policy is used to fight inflation?
8Recap Recap
- The business cycle is real GDP fluctuating around its long-run trend, giving rise to inflation, deflation and unemployment
- Real rate ≈ nominal rate minus inflation; inflation redistributes wealth between creditors and debtors
- Quantity theory: with velocity unchanged, money-supply growth translates proportionally into price rises
- Unemployment rate = unemployed ÷ labour force; unemployment and underemployment both mean lost output and wasted human resources
- Fiscal policy moves spending and taxes; monetary policy moves money supply and rates — both work through aggregate demand