Black Monday marked the 1987 global stock-market crash when the Dow Jones Industrial Average fell 22.6 percent.
The date was October 19, 1987. The Dow lost 508 points, then the largest one-day point decline in its history and its largest one-day percentage loss ever. Selling spread rapidly to markets in Europe, Asia, Australia, and elsewhere, making the event a genuinely global crash.
Several pressures were involved, including overvalued shares, trade and currency concerns, rising interest rates, and computerized portfolio-insurance strategies. These automated or rule-based selling systems may have amplified the downward movement, though historians and economists do not attribute the crash to one universally accepted cause.
Black Monday did not lead to a depression comparable to the 1930s. The U.S. economy continued expanding, and the Dow recovered much of its loss in the following months. The crash nevertheless prompted major changes in market safeguards, including circuit breakers designed to pause trading during extreme declines.