The 1987 market crash is known as Black Monday because of the worldwide one-day equity sell-off on October 19.
The panic began in markets in Asia and spread through Europe before reaching the United States. The Dow Jones Industrial Average lost 22.6%, while other major indexes also recorded exceptional declines.
Analysts have identified several contributing conditions, including high valuations, concerns about interest rates and trade, and automated selling strategies. No single cause fully explains the speed and size of the fall.
The name Black Monday can cause confusion because it is also used for other market disasters, including the 1987 Hong Kong crash and the 1987 New Zealand crash. In international financial history, however, the term most commonly refers to the global equity collapse of October 19, 1987.