The Dow Jones Industrial Average suffered a 998.5-point loss during the 2010 flash crash.
On May 6, 2010, the Dow plunged about 1,000 points in minutes, briefly erasing nearly $1 trillion in market value before recovering much of the loss. The extreme movement affected U.S. equities, futures, exchange-traded funds, and individual stocks.
Investigations attributed the event to a combination of existing market stress, high-frequency trading, automated orders, and a large sell order. The precise interaction of those factors allowed liquidity to disappear rapidly and caused some securities to trade at bizarre prices.
The event differed from a conventional crash because much of the fall reversed within the same session. It led regulators and exchanges to adopt circuit breakers and other safeguards intended to slow disorderly automated selling.