On what date did the 1987 global stock-market crash reach its famous U.S. trading-day low?

The 1987 global stock-market crash reached its famous U.S. trading-day low on October 19, 1987.

That Monday became known as Black Monday after the Dow Jones Industrial Average fell 508 points, or 22.6%, in a single session. It was the largest one-day percentage decline in the Dow’s history and followed sharp falls in markets across Asia and Europe.

The crash was associated with several pressures, including overvalued shares, rising interest rates, computerized trading strategies, portfolio insurance, and international market tensions. The exact causes remain debated, so it is misleading to attribute the collapse to one single event.

Black Monday is not the same as Black Tuesday, October 29, 1929, a major day in the earlier Wall Street Crash. After 1987, regulators introduced coordinated safeguards, including trading halts and circuit breakers, to slow future collapses.