The Dow Jones Industrial Average suffered its largest-ever one-day point loss during the 2010 Flash Crash on May 6, 2010.
During the afternoon of May 6, U.S. equity markets experienced an exceptionally rapid fall and partial rebound. The Dow dropped about 1,000 points, roughly 9%, within minutes before recovering much of the decline. Prices in individual stocks, exchange-traded funds, and futures contracts became extremely volatile, and some trades occurred at wildly unusual prices.
Investigations identified a large automated sell order in S&P 500 futures as an important trigger, while high-frequency trading and fragmented market liquidity amplified the movement. The U.S. Securities and Exchange Commission and Commodity Futures Trading Commission later described a feedback loop in which selling, hedging, and withdrawal of liquidity reinforced one another.
The Flash Crash was not the same as a conventional multi-month bear market. It was a market-structure event focused on speed, electronic trading, and liquidity. New safeguards, including circuit breakers and single-stock trading limits, were introduced or strengthened afterward.