CFA Level I Exam · Understanding Business Cycles
Theories of the Business Cycle: Keynesian, Monetarist, Austrian and RBC
Updated 7 October 2026 · Fact-checked
Business cycle theories explain why output and employment fluctuate. Neoclassical economists say markets self-correct. Keynesians blame swings in aggregate demand. Monetarists blame money supply growth. Austrians blame credit expansion by central banks. Real business cycle theorists blame real shocks such as technology. To answer exam questions, find the stated cause and match it to the school.
Understand Theories of the Business Cycle
A business cycle is the recurring pattern of expansion and contraction in economic activity. The theories differ on one question: what causes the swings, and should policy respond? Your exam task is usually to match a statement to a school.
Neoclassical view: prices and wages adjust, so markets return to full employment on their own. Downturns are temporary and policy intervention is not needed. This is the baseline the other schools react to.
Keynesian view: swings come from changes in aggregate demand, driven by waves of optimism and pessimism among businesses and consumers. Wages and prices are slow to adjust (sticky), so a demand drop can leave the economy below full employment for a long time. Keynesians support active fiscal and monetary policy to stabilize demand. New Keynesians incorporate rational expectations and explain sticky wages and prices through firms' behaviour, such as menu costs and contracts.
Monetarist view: the cause is the money supply. Steady, predictable money growth gives stable growth. Excess money growth causes inflation, and too little causes recession. Monetarists argue against discretionary policy and favour a fixed rule for money growth, because policy timing is unreliable.
Austrian view: cycles come from government and central bank intervention. Artificially low interest rates encourage excess credit and unsustainable investment in long-term projects. The boom later ends in a bust as the mistakes are exposed. Austrians oppose intervention.
Real business cycle (RBC) view: cycles are caused by real shocks, mainly changes in technology and productivity, not by money or demand. Workers and firms respond rationally, so fluctuations are efficient responses and policy is unnecessary or harmful. RBC is a modern school built on the Neoclassical tradition.
How to solve Theories of the Business Cycle questions
No calculation is needed. Use this method to classify any question on cycle theories.
- 1Read the stem and underline the claimed cause of the cycle: demand, money supply, credit and interest rates, or real shocks.
- 2Match the cause: demand swings and sticky prices point to Keynesian; money supply points to Monetarist; artificially low rates and credit boom point to Austrian; technology or productivity shocks point to RBC; self-correcting markets point to Neoclassical.
- 3Check the policy view in the stem: active stabilization (Keynesian), fixed money growth rule (Monetarist), no intervention (Austrian, RBC, Neoclassical).
- 4Check the assumption on wages and prices: sticky (Keynesian) versus flexible (Neoclassical, RBC).
- 5Eliminate the two options that name the wrong cause or wrong policy stance, then choose the remaining one.
Quickest way: Cause-and-policy keyword match
When to use it: Any three-option question asking which school or view a statement reflects.
- Spot the keyword: demand, money supply, credit, or technology.
- Recall the pair: demand = Keynesian, money = Monetarist, credit = Austrian, technology = RBC.
- Cross out options with a different cause.
- If two remain, use the policy stance to decide.
Common mistakes in Theories of the Business Cycle
Confusing Monetarists with Keynesians because both discuss monetary policy.
Both schools say money matters.
Fix: Monetarists focus on money supply growth and favour a fixed rule. Keynesians focus on aggregate demand and favour active policy.
Saying RBC theory blames demand or money shocks.
The word cycle suggests demand-driven swings.
Fix: RBC attributes cycles to real shocks, mainly technology, and sees policy as unnecessary.
Treating the Austrian view as the same as Monetarism.
Both criticize central banks.
Fix: Austrians blame artificially low interest rates and credit expansion causing malinvestment. Monetarists blame erratic money supply growth.
Assuming Keynesians believe wages and prices adjust quickly.
Mixing up with the Neoclassical view.
Fix: Keynesians stress sticky wages and prices. Neoclassical and RBC assume flexible adjustment.
Believing RBC implies recessions are inefficient and need stimulus.
Applying a Keynesian lens.
Fix: RBC sees fluctuations as rational, efficient responses to real shocks, so stimulus is not called for.
Worked examples
Example 1
An economist argues that recessions occur when central banks hold interest rates artificially low, fuelling credit growth and investment in unsustainable projects. Which school does this reflect? A. Austrian B. Monetarist C. Real business cycle
Show the solution
- Cause stated: artificially low rates and credit expansion leading to unsustainable investment.
- Monetarists blame money supply growth and favour a fixed rule, not malinvestment from low rates, so B does not fit.
- RBC blames real shocks like technology, so C is wrong.
- The credit-boom and malinvestment story is the Austrian explanation.
Answer: A. Austrian
Example 2
A analyst says output fell because a new technology raised productivity in one sector and workers rationally reallocated their effort, so no government stimulus is needed. Which view is this? A. Keynesian B. Real business cycle C. Monetarist
Show the solution
- Cause stated: a real technology shock, with rational responses.
- Keynesians stress demand and sticky prices and support stimulus, so A is out.
- Monetarists focus on money supply, so C is out.
- Real shocks and no policy response match RBC theory.
Answer: B. Real business cycle
Exam tips
- Memorize one cause per school: demand, money, credit, technology, self-correction.
- Policy stance is a strong tie-breaker: active (Keynesian) versus rule or no intervention (others).
- Watch for the word sticky; it signals Keynesian thinking.
- Questions are standalone three-option items, so eliminate the two options with the wrong cause and answer quickly.
Practice questions from Understanding Business Cycles
- A manufacturing region loses many jobs because its industry is replaced by automation, and the displaced workers lack the skills needed for …
- At the start of an economic slowdown, retailers see sales fall below expectations. The inventory-to-sales ratio most likely:
- During which phase of the business cycle are economic activity, such as output and employment, most likely to be at their lowest level befor…
- According to Keynesian business cycle theory, a recession is most likely prolonged because:
- During the late expansion phase of a business cycle, as output approaches its capacity limit, which of the following changes in resource use…
Theories 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.
Theories of the Business Cycle: frequently asked questions
What is the difference between Keynesian and Monetarist business cycle views?
Keynesians say cycles come from shifts in aggregate demand and support active fiscal and monetary policy. Monetarists say cycles come from money supply changes and prefer steady, rule-based money growth.
What is real business cycle theory?
RBC theory says fluctuations are caused by real shocks, mainly changes in technology and productivity. Because agents respond rationally, the swings are efficient and policy intervention is not needed.
What does the Austrian school say about business cycles?
Austrians say central bank intervention keeps interest rates artificially low. This encourages excess credit and investment in unsustainable projects, which leads to a bust.
Do I need formulas for this topic?
No. It is conceptual. You must match each theory to its cause of cycles and its policy stance.