The first major trading day of the 1987 global stock-market crash, October 19, was called Black Monday.
The name refers to the day of the week on which markets around the world suffered extraordinary losses. In New York, the Dow Jones Industrial Average dropped 22.6%, its largest one-day percentage decline. Major markets in Europe, Asia, and elsewhere also fell, making the event distinctly international.
The decline followed a period of strong gains and rising anxiety about interest rates, currency policy, trade tensions, and market valuations. Computerized trading strategies were still relatively new, but their automatic selling mechanisms were widely blamed for amplifying the fall.
Black Monday is sometimes confused with the Black Monday of October 28, 1929, which preceded Black Tuesday in the earlier Wall Street Crash. The same label is used for more than one historical market event, so the year is essential when identifying the 1987 crash.