The global stock-market collapse that began in October 1987 is known as Black Monday.
On October 19, 1987, markets around the world fell sharply. The Dow Jones Industrial Average dropped 508 points, or 22.6 percent, its largest one-day percentage decline. Major markets in Europe, Asia and the Pacific also recorded severe losses, making the event international rather than solely American.
Several factors were discussed, including rising interest rates, a widening U.S. trade deficit, investor concerns about currency values and computerized trading strategies. Portfolio insurance programs could generate additional selling as prices declined, although historians and economists do not attribute the crash to one universally accepted cause.
The crash did not produce a depression comparable to the 1930s. Central banks supplied liquidity, and markets eventually recovered. Regulators also introduced or strengthened mechanisms such as trading halts, commonly called circuit breakers, to slow panic during exceptionally rapid declines. Black Monday is distinct from the 1929 crash and from the 2008 financial crisis.