What was the fastest stock-market bear market in U.S. history, lasting only 23 trading days in 2020?

The COVID-19 market crash was the fastest U.S. stock-market bear market, lasting only 23 trading days in 2020.

The S&P 500 entered bear-market territory on March 12, 2020, after global markets reacted to the rapid spread of COVID-19, travel restrictions, business closures, and uncertainty about economic activity. The index reached its closing low on March 23, after falling about 33.9 percent from its February 19 record close.

The decline was unusually rapid compared with earlier U.S. bear markets. Governments and central banks responded with emergency fiscal programs, interest-rate cuts, asset purchases, and lending facilities. Those measures, followed by changing expectations about vaccines and reopening, helped equities rebound sharply.

A bear market is conventionally defined as a decline of at least 20 percent from a recent closing high. The 23-trading-day figure refers to the S&P 500’s move into bear-market territory, not the entire period of market volatility or the full economic recession.