Black Monday caused the Dow Jones Industrial Average to fall 22.6% in one day in 1987.
The crash occurred on October 19, 1987, when the Dow lost 508 points, then its largest one-day point decline. Stock markets in several countries also plunged, making the event a genuinely global crash rather than an isolated New York episode.
Analysts have linked the collapse to overvalued shares, rising interest rates, trade tensions and computerized program trading. Portfolio insurance strategies could amplify selling when prices fell, although no single explanation fully accounts for the scale of the move.
Black Monday is often confused with the 1929 crash’s Black Tuesday. The two events were separated by 58 years, and the percentage fall in 1987 was much larger for the Dow. Markets recovered relatively quickly compared with the prolonged decline after 1929.