The 2010 Flash Crash occurred on May 6, 2010, when U.S. stock markets plunged rapidly and then recovered much of the loss.
The Dow Jones Industrial Average dropped about 1,000 points, nearly 9%, in a matter of minutes. Some individual securities briefly traded at extraordinarily low prices before the market stabilized. The speed and irregularity of the move drew attention to electronic trading, automated strategies, liquidity, and market safeguards.
A joint investigation by U.S. regulators concluded that a large sell order in E-mini S&P 500 futures interacted with high-frequency trading and stressed market liquidity. The event was not simply a conventional panic in which investors gradually sold shares; its defining feature was the extreme speed of the price movement.
The crash led to changes including circuit breakers and rules for handling clearly erroneous trades. It also became a major case study in the risks and complexities of highly automated markets.