The 1987 global stock-market crash reached its famous U.S. “Black Monday” on October 19, 1987.
The Dow Jones Industrial Average fell 508 points that day, a loss of 22.6 percent, then the largest one-day percentage decline in the index’s history. Major markets in Europe, Asia, Australia, and Canada also suffered steep losses, making the event an international crash rather than an isolated Wall Street decline.
Economists and historians point to several contributing factors, including high valuations, rising interest rates, trade tensions, and computerized portfolio-insurance selling. The exact cause remains debated, but the scale of automated selling clearly intensified the plunge.
Black Monday is often confused with the 1929 crash days called Black Thursday, Black Monday, and Black Tuesday. The 1987 event was followed by market reforms, including circuit breakers designed to slow trading during extreme falls.