The S&P 500 recorded its fastest bear-market decline from a peak on March 23, 2020, during the 2020 stock-market crash.
The crash followed the global spread of COVID-19 and the economic restrictions introduced to slow transmission. Investors rapidly repriced airlines, energy companies, banks, and other businesses exposed to falling demand and disrupted supply chains. The S&P 500 entered a bear market on March 12, after falling at least 20% from its February 19 record close.
March 23 marked the closing low for the major U.S. indexes in the initial pandemic sell-off. The S&P 500 then rebounded strongly as central banks and governments announced large-scale support and investors anticipated economic reopening. Volatility remained high, and the recovery was uneven across industries.
The date is sometimes confused with March 9, March 12, or March 16, all of which brought major declines. March 23 specifically identifies the 2020 S&P 500 closing low in the initial crash.