The 2020 COVID-19 stock-market crash produced the S&P 500’s shortest bear market, lasting 33 days.
The bear market began on February 19, 2020, when the S&P 500 closed at a record high, and ended on March 23, when the index reached its pandemic-era closing low. Over that interval, the index fell about 34%, satisfying the usual bear-market definition of a decline of at least 20% from a recent closing high.
The collapse reflected the rapid spread of COVID-19, business shutdowns, travel restrictions, supply disruptions, and extreme uncertainty about economic activity. Financial markets also reacted to an oil-price shock and stress in credit markets. Governments and central banks responded with large fiscal programs, emergency lending, interest-rate cuts, and asset purchases.
The 33-day duration measures the S&P 500 bear-market phase, not the entire economic recession or the complete period of market volatility. The index recovered unusually quickly after March 2020, although the public-health crisis and its economic effects continued for much longer.