The May 6, 2010 U.S. stock-market plunge was called the 2010 Flash Crash.
During the event, the Dow Jones Industrial Average dropped about 1,000 points, or roughly 9%, in a very short period. Several major stocks and exchange-traded funds briefly traded at extremely low prices before much of the decline reversed.
Investigations attributed the crash to interactions among high-frequency trading, algorithmic orders, market liquidity, and a large sell order. The U.S. Securities and Exchange Commission and the Commodity Futures Trading Commission concluded that automated trading activity helped accelerate the fall.
The Flash Crash is sometimes confused with a conventional bear market because the decline was dramatic, but it was unusually rapid and largely recovered the same day. Regulators later introduced safeguards, including circuit breakers and rules for clearly erroneous trades.