The 1987 stock-market crash named for the weekday of the Dow’s 22.6% fall was Black Monday.
On October 19, 1987, the Dow Jones Industrial Average dropped 508 points, or 22.6 percent, in its largest one-day percentage decline. Markets in Hong Kong, Europe, Australia, and elsewhere also suffered major losses, making the event an international crash rather than an isolated U.S. episode.
Researchers have identified several contributing factors, including high valuations, rising interest rates, trade tensions, and computerized portfolio-insurance strategies. These automated selling systems could intensify a decline, although no single cause explains every market movement. Black Monday is often confused with the 1929 crash dates, but the 1987 event occurred nearly six decades later. The crash also led regulators to develop coordinated trading halts, including circuit breakers, intended to slow future episodes of extreme volatility.