The S&P 500 fell approximately 34% from February 19 to March 23, 2020.
The decline was part of the 2020 stock-market crash, which began as investors reacted to the global spread of COVID-19 and the prospect of severe economic restrictions. The S&P 500 reached a record closing high on February 19 before entering a remarkably rapid bear market.
During the fall, markets experienced repeated one-day losses large enough to trigger circuit breakers. Oil-price tensions, disruptions to travel and supply chains, and uncertainty about corporate earnings added to the pressure. Governments and central banks responded with emergency fiscal and monetary measures.
The market subsequently recovered much of its decline, helped by policy support, vaccine developments, and expectations of economic reopening. A market crash is therefore not the same as a permanent loss: prices can rebound even while unemployment, business closures, and other economic damage remain severe. The 2020 episode was unusually fast compared with many earlier crashes.