March 16, 2020, marks the biggest one-day percentage fall in the S&P 500 during the COVID-19 crash.
The S&P 500 dropped 12.0 percent on March 16, 2020, as investors reacted to the rapidly spreading COVID-19 pandemic, travel restrictions, business closures, and growing uncertainty about economic activity. It was the index's worst percentage decline since Black Monday in 1987.
The 2020 crash unfolded unusually quickly. Trading was halted several times by market-wide circuit breakers, including during the March 16 session. Central banks and governments then announced extensive monetary, fiscal, and public-health responses. Markets later rebounded sharply, though the economic effects remained uneven across countries and industries.
March 9 and March 12 were also exceptionally volatile sessions, which can cause confusion when comparing records. March 16 is the specific date associated with the S&P 500's largest one-day percentage loss in the COVID-era crash.