In the 2020 stock-market crash, the S&P 500 took 16 trading days to fall 20% from its record high.
The index reached a record closing high on February 19, 2020, before concerns about the spread of COVID-19 intensified worldwide. By March 12, the S&P 500 had entered a bear market, defined in this context as a decline of at least 20% from a recent peak.
This was the fastest bear-market entry in the S&P 500’s history at that time. The collapse reflected fears about the pandemic, business closures, travel restrictions, supply-chain disruption, and the economic consequences of containment measures.
The 2020 crash was unusually sharp but relatively brief. Massive fiscal support, central-bank intervention, improving vaccine prospects, and reopening expectations helped markets recover later that year. The bear-market threshold is different from a market correction, which commonly means a decline of at least 10% but less than 20%.