CFA Level I Exam · Understanding Business Cycles

Phases of the Business Cycle: Expansion, Peak, Contraction, Trough

Updated 7 October 2026 · Fact-checked

The business cycle is the recurring pattern of economic activity moving through expansion, peak, contraction and trough. Expansion means rising output, jobs and spending. The peak is the turning point to decline. Contraction means falling activity. The trough is the low point before recovery. To answer questions, match the data to the phase.

Understand Phases of the Business Cycle

The business cycle is the repeated rise and fall of overall economic activity around a long-term growth trend. It is not a fixed timetable. Cycles differ in length and depth, and they are not perfectly predictable.

There are four phases. In an expansion, real GDP rises, employment grows, consumer and business spending increase, and capacity use goes up. Inflation often starts to rise later in the expansion. The peak is the upper turning point, where activity stops rising and starts to fall. At the peak, the economy is typically running hot, with high capacity use, tight labour markets and rising inflation pressure.

In a contraction (also called a recession when it is severe), real GDP falls, firms cut hiring and investment, and unemployment rises. Inflation tends to ease. The trough is the lower turning point where activity stops falling and begins to rise. Unemployment is often still high at the trough, because jobs usually recover after output does.

The curriculum also describes the early part of an expansion as a recovery, and the late part as a period where the economy approaches its limits. Cyclical sectors, such as autos, housing and capital goods, swing more than defensive sectors like food and utilities.

The cycle is described using economic indicators: real GDP, employment, industrial production, capacity utilization, inflation and sentiment. Some indicators lead the turning points, some move with them, and some lag. Recession definitions vary by country. A common shorthand is two consecutive quarters of falling real GDP, but many official bodies use broader judgement across several measures, so do not treat the shorthand as universal.

Key formulas to remember

Expansion: Trough → Peak: real GDP rising; Employment, spending, investment and capacity utilization rise. Inflation tends to rise late in the phase.
Contraction: Peak → Trough: real GDP falling; Output, hiring and investment fall. Inflation pressure usually eases. Unemployment rises.
Peak: Upper turning point; Growth stops and reverses. Capacity use and inflation pressure are typically high.
Trough: Lower turning point; Decline stops and recovery starts. Unemployment often still high or still rising.
Real GDP growth: Growth rate = (GDP this period − GDP prior period) ÷ GDP prior period; Use real, not nominal, GDP to judge the phase.

How to solve Phases of the Business Cycle questions

Use this method for any question that asks you to identify a phase or describe its features.

1Read the stem and list every data point given: GDP, jobs, inflation, capacity use, spending, sentiment.
2Check whether the data describe a level or a direction. Phases are defined by direction of activity, turning points by change of direction.
3Decide the direction of real GDP. Rising means expansion, falling means contraction.
4Look for a turning point clue: growth just slowing from high levels points to a peak; decline just flattening points to a trough.
5Use lagging details to confirm. High unemployment with output starting to rise suggests early expansion or trough. Tight labour and rising inflation suggest late expansion or peak.
6Eliminate the two options that contradict the GDP direction, then pick the one that fits the other details.

Quickest way: Direction first, turning point second

When to use it: Use when you have about 90 seconds and the stem lists several economic data points.

Find real GDP direction. This removes at least one option.
Ask: is it just turning? Words like 'stopped', 'began to' signal a peak or trough.
Check inflation and capacity use as clues only: high capacity use with rising inflation pressure points toward a peak; low capacity use with low or falling inflation is a typical clue near a trough. Inflation lags output, so it can still be high at a trough. Treat it as supporting evidence, not proof.
Pick the option consistent with both, and do not over-think. There is no penalty for guessing.

Common mistakes in Phases of the Business Cycle

Calling the peak the 'strongest' part of the cycle and expecting growth to be fastest there.
Level of activity is highest at the peak, so students confuse it with the fastest growth.
Fix: At the peak, the level is highest but growth is turning to zero or negative. Fastest growth is often earlier in the expansion.
Assuming unemployment falls as soon as the trough is reached.
Students link output and jobs too tightly.
Fix: Employment is a lagging indicator. Unemployment often stays high or rises for a while after output begins to recover.
Treating 'two quarters of falling GDP' as the universal definition of recession.
It is a popular shortcut in news and textbooks.
Fix: Present it as a common rule of thumb. Official dating often uses a broader set of indicators.
Using nominal GDP to judge the phase.
Inflation can make nominal GDP rise even when real output falls.
Fix: Always use real GDP, adjusted for inflation.
Mixing up the trough and the contraction.
Both involve weak data.
Fix: Contraction is the falling phase between peak and trough. The trough is only the turning point at the bottom.

Worked examples

Example 1

An economy reports that real GDP fell for the third straight quarter, firms are cutting capital spending, unemployment is rising, and inflation is slowing. Which phase is the economy most likely in?
A. Expansion
B. Peak
C. Contraction

Show the solution

Real GDP is falling, which means activity is declining. This rules out expansion (A).
The peak is the turning point where activity stops rising and starts to fall. Output has already been falling for three quarters, so the peak has passed and the economy is in the contraction phase, not at the turning point (rules out B).
Falling investment, rising unemployment and easing inflation are all typical of contraction.

Answer: C. Contraction

Example 2

Real GDP grew in the last two quarters after a long decline. Capacity utilization is low, inflation is near its lowest level in years, and unemployment remains high. Which description fits best?
A. Early expansion, just after the trough
B. Late expansion, near the peak
C. Contraction

Show the solution

Real GDP is rising, so the economy is not in contraction (rules out C).
Low capacity use and very low inflation mean there is plenty of slack. A late expansion would show high capacity use and rising inflation pressure (rules out B).
High unemployment is consistent with early recovery, because jobs lag output.

Answer: A. Early expansion, just after the trough

Exam tips

Always anchor on real GDP direction first, then use inflation, capacity use and labour data to refine.
Remember lags: unemployment and inflation turn after output, so mixed signals often point to a turning-point phase.
Distinguish phases (expansion, contraction) from turning points (peak, trough) in the answer options.
Link cycle phases to sector behaviour: cyclical sectors swing more, defensive sectors hold up better.
Do not spend more than the suggested time; if two options remain, choose the one matching the most data points.

Practice questions from Understanding Business Cycles

Phases of the Business Cycle in other exams

The same ground in other exams, if you are preparing for more than one or want another angle on it.

Phases of the Business Cycle: frequently asked questions

What are the four phases of the business cycle?

They are expansion, peak, contraction and trough. Expansion and contraction are periods of rising and falling activity. Peak and trough are the turning points at the top and bottom.

What is the difference between a contraction and a recession?

A contraction is the general phase of falling activity between a peak and a trough. A recession is a significant, broad and lasting contraction. Definitions of recession vary by country.

Does unemployment peak at the trough?

Not necessarily. Unemployment is a lagging indicator, so it often keeps rising or stays high for some time after output starts to recover.

How is the business cycle measured?

It is described using indicators such as real GDP, employment, industrial production, capacity utilization and inflation. Some indicators lead turning points, some coincide and some lag.