Which U.S. stock-market day in 1987 became known as Black Monday?
Answer
October 19, 1987
The U.S. stock-market day known as Black Monday in 1987 was October 19, 1987.
On that date, the Dow Jones Industrial Average fell 508 points, or 22.6%, its largest one-day percentage decline. Selling spread rapidly across international markets, making the event a global stock-market crash rather than an isolated New York decline.
Several factors were discussed afterward, including rising interest rates, a growing trade deficit, investor anxiety, and computerized portfolio-insurance strategies. Those automated selling programs could amplify a falling market by placing additional sell orders as prices dropped.
Black Monday is often confused with Black Tuesday in 1929. Black Monday refers specifically to October 19, 1987, while Black Tuesday refers to October 29, 1929. Regulators later introduced circuit breakers designed to pause trading during exceptionally rapid declines.