Which 1987 stock-market crash is named for the weekday October 19, 1987?

The 1987 stock-market crash is known as Black Monday because the biggest global selling wave occurred on Monday, October 19, 1987.

On that day, the Dow Jones Industrial Average fell 22.6%, its largest one-day percentage decline in history. Markets in other countries also plunged, making the event an international crash rather than a crisis confined to the United States.

Several factors were associated with the collapse, including high share valuations, a slowing economy, rising interest rates, and computerized portfolio-insurance trading. Automated selling could reinforce falling prices, although no single explanation accounts for every market movement.

Black Monday is not the same event as the Black Monday of October 28, 1929. The repeated name simply reflects the weekday and the scale of the losses. The 1987 crash also differed from 1929 because markets recovered more quickly and the episode did not lead to a Depression on the earlier scale.