What macroeconomic theory attributes business cycles to real shocks, such as changes in technology or productivity?

Real business cycle theory attributes business-cycle fluctuations primarily to real shocks, such as changes in technology, productivity, weather, regulation, or energy prices.

The theory emerged in modern form from Finn Kydland and Edward Prescott’s 1982 work, which modeled fluctuations as responses to productivity shocks within a competitive economy. In a basic real business cycle model, households and firms respond optimally to changing productive conditions. A favorable technology shock can raise output, investment, consumption, and labor, while a negative shock can produce a downturn.

The word “real” distinguishes these explanations from nominal shocks involving money, prices, or monetary policy. RBC models generally treat markets as clearing and interpret observed fluctuations as efficient responses to altered economic conditions, rather than chiefly as failures caused by weak demand. This implication has often led proponents to favor limited discretionary stabilization policy.

Critics argue that the theory requires very large or implausible productivity shocks and has difficulty explaining involuntary unemployment, financial crises, and demand-driven recessions. Keynesian models instead emphasize insufficient aggregate demand, while Minsky’s hypothesis focuses on financial instability. RBC theory remains an important benchmark, even where economists reject its strongest assumptions.