The S&P 500 entered a bear market in 2020 after the fastest 30% fall from a record high.
The decline was driven by the COVID-19 pandemic, which disrupted travel, commerce, employment, and supply chains. From its February 19, 2020 record close to its March 23 low, the index fell about 34%, reaching bear-market territory in one of the quickest modern market sell-offs.
Central-bank support, government fiscal programs, and hopes for vaccines helped produce a powerful rebound later in 2020. The crash is often confused with a normal recession-driven decline, but its speed was exceptional and directly reflected the sudden global public-health shock. The S&P 500 tracks 500 large U.S. companies and is widely used as a benchmark for American equities.