Questions: Nominal and Real Macroeconomic Variables

Question 1

A country's nominal GDP grows from $1 trillion to $1.2 trillion in one year — a 20% increase. Over the same period, the GDP deflator rises from 100 to 125, indicating 25% inflation. What happened to real GDP?

• A. Real GDP grew by 20%, because that is what the nominal figures show
• B. Real GDP grew by 5%, because the real growth equals nominal growth minus inflation
• C. Real GDP fell by approximately 4%, because the price level grew faster than nominal output
• D. Real GDP is unchanged, because the deflator adjusts for the nominal increase exactly

Answer: (C)

Real GDP = Nominal GDP / Price Index × 100. At the start: $1T / 100 × 100 = $1T real. At the end: $1.2T / 125 × 100 = $0.96T real. Real GDP fell by about 4% — the economy produced *less* in real terms even though nominal GDP rose sharply. This is the core trap the nominal/real distinction protects against: strong nominal growth during high inflation can mask a contracting real economy. Citizens are not 20% better off; they are worse off. This scenario describes what happens in high-inflation episodes: nominal figures soar while real activity stagnates or collapses.

Question 2

A bank offers a savings account paying 6% nominal interest. Inflation is running at 4%. A business is deciding whether to borrow at this rate to fund a capital investment expected to return 3% in real terms. Should the business borrow?

• A. Yes — the nominal interest rate (6%) is higher than the real return (3%), so the investment is profitable
• B. No — the real interest rate (approximately 2%) is lower than the real return (3%), so the investment is profitable and the business should proceed
• C. No — the real interest rate (approximately 2%) is lower than the real return (3%), making borrowing attractive, but the business should wait for nominal rates to fall
• D. No — the real interest rate exceeds the real return (6% > 3%), so borrowing costs more than the investment earns

Answer: (B)

The Fisher equation: real interest rate ≈ nominal rate − inflation = 6% − 4% = 2%. The real cost of borrowing is 2%, and the real return on the investment is 3%. Since the real return (3%) exceeds the real cost (2%), the investment is profitable in purchasing-power terms — the business earns more in real terms than it pays. Comparing nominal rates to real returns (as in options A and D) is a category error: you must compare real to real. The nominal rate of 6% is misleading here because 4% of it is simply compensating for inflation on both sides of the transaction.

Question 3

A worker receives a 10% nominal wage increase this year. Since their paycheck is larger, their purchasing power has necessarily increased.

• T. True
• F. False

Answer: False

Purchasing power depends on real wages, not nominal wages. If inflation was 12% over the same period, the worker's nominal wage rose 10% but prices rose 12% — meaning the worker can actually buy *less* with their larger paycheck than before. Their real wage fell by approximately 2%. A nominal wage increase only increases purchasing power if it exceeds inflation. This is why workers, unions, and economists focus on real wage growth rather than nominal wage growth: the nominal figure is only the starting point, not the answer.

Question 4

Rising nominal GDP is not sufficient evidence that an economy is producing more goods and services, because nominal GDP can rise due to inflation even with no change in real output.

• T. True
• F. False

Answer: True

This is the core motivation for the real/nominal distinction. If an economy produces exactly the same quantities of everything this year as last year but all prices rise by 10%, nominal GDP rises by 10% with zero increase in actual output. The measuring stick (money) changed in value, not the underlying economic activity. To assess whether an economy is genuinely producing more, you must use real GDP, which adjusts for price-level changes to express output in constant base-year prices. During high-inflation periods, nominal GDP can rise dramatically while real GDP stagnates or contracts.

Question 5

Why do real interest rates — rather than nominal interest rates — govern saving and investment decisions?

Model answer: A nominal interest rate bundles together two things: the real return on saving or real cost of borrowing, plus compensation for expected inflation. Inflation erodes the purchasing power of money equally on both sides of a transaction. If you lend $1,000 at 6% nominal and inflation is 4%, you receive $1,060 at the end of the year — but those dollars buy only as much as $1,019 did at the start (because prices rose 4%). Your real return is approximately 2%, not 6%. A business evaluating an investment cares whether its real return exceeds the real cost of borrowing — that is what determines whether the project creates genuine value. If a project earns 3% in real terms and the real borrowing cost is 2%, it is profitable; if the real cost is 5%, it is not — regardless of what the nominal rate is.

The Fisher equation (real rate ≈ nominal rate − inflation) makes explicit that the nominal rate is the surface measure and the real rate is the economically relevant one. This is also why monetary policy operates on real rates: a central bank that raises nominal interest rates during a period of high inflation may actually be keeping real rates low or negative, which is stimulative rather than contractionary — the nominal number can be misleading about the policy's actual effect.