The Dow Jones Industrial Average fell 998.5 points during the 2010 Flash Crash.
On May 6, 2010, U.S. markets experienced a rapid and extraordinary plunge followed by a substantial recovery. The Dow fell about 9% from the previous close, and its 998.5-point decline was the largest one-day point drop at that time. The event unfolded within minutes rather than through a full trading session of steadily worsening news.
Investigations found that automated trading, market conditions, and a large sell order contributed to the episode. The U.S. Securities and Exchange Commission and the Commodity Futures Trading Commission concluded that the selling interacted with existing fragility in electronic markets. Many securities briefly traded at extremely abnormal prices.
The crash exposed weaknesses in market structure rather than representing a conventional economic collapse like 1929 or 2008. Regulators later introduced measures including circuit breakers and mechanisms designed to slow disorderly price movements. The Dow’s point record was eventually surpassed as the index’s numerical level rose.