In popular economic usage, how many consecutive quarters of falling real GDP define a recession?

In popular economic usage, two consecutive quarters of falling real GDP define a recession.

This is a widely repeated rule of thumb because gross domestic product measures the value of goods and services produced, while real GDP removes the effect of changing prices. Two quarterly declines therefore suggest that inflation-adjusted economic activity has contracted for about six months.

The rule is not a universal official definition. In the United States, the National Bureau of Economic Research examines a broader set of indicators, including employment, income, industrial production and sales, and identifies the timing of monthly peaks and troughs.

A recession can therefore be declared even when GDP does not fall for exactly two quarters. Conversely, a short technical GDP decline may not be judged a full recession if other economic measures remain strong.