The most infamous trading day of the 1987 global stock-market crash was nicknamed Black Monday.
Black Monday occurred on October 19, 1987, when stock markets around the world fell sharply. In the United States, the Dow Jones Industrial Average lost 22.6% of its value in a single session, a record percentage decline that remains widely cited.
The name was also used for the same date in several other countries, even though time zones meant some markets experienced the fall on their Tuesday. Hong Kong and London were among the major markets hit by the international selling wave.
Black Monday is distinct from Black Tuesday in 1929, the date most associated with the Wall Street Crash of 1929. The similar names reflect a long tradition of using “black” labels for unusually disastrous financial days, not a direct connection between the two crashes.