During the 2010 Flash Crash, the Dow Jones Industrial Average lost about 998.5 points intraday before most of the fall reversed.
On May 6, 2010, U.S. stock indexes dropped sharply within minutes. The Dow’s decline was about 9% at its worst point, and many individual securities experienced extraordinary temporary price movements. Some trades occurred at prices far outside normal levels before markets stabilized.
Investigations concluded that the event involved a combination of existing market stress, automated trading, and a large sell order in E-mini S&P 500 futures. High-frequency trading firms and other market participants interacted in ways that rapidly reduced liquidity. Authorities later charged trader Navinder Singh Sarao with contributing to the episode through spoofing activity, though the broader event had multiple mechanisms.
The crash led U.S. regulators and exchanges to introduce or strengthen safeguards, including circuit breakers and single-stock trading pauses. It demonstrated how electronic markets can move extremely quickly even without a conventional economic panic.