The 1987 worldwide market crash that began in Hong Kong before spreading westward was called Black Monday.
On October 19, 1987, stock markets around the world suffered exceptionally large one-day declines. The Dow Jones Industrial Average fell 22.6 percent, while markets in Hong Kong, Europe, Australia and Canada also recorded severe losses.
The Hong Kong market had begun falling before the U.S. session, and selling pressure moved westward through international time zones. Researchers have linked the crash to overvaluation, rising interest rates, trade concerns and computerized portfolio-insurance strategies, although no single explanation accounts for every market’s movement.
Black Monday is distinct from the 1929 Wall Street crash, even though both involved dramatic U.S. equity declines. The 1987 episode did not produce a depression comparable to the 1930s. Exchanges subsequently strengthened coordination and developed circuit breakers intended to slow exceptionally rapid sell-offs.