What was the name of the 1987 market crash’s largest single-day percentage drop?

Black Monday was the name of the 1987 market crash’s largest single-day percentage drop.

Black Monday occurred on October 19, 1987, when stock markets around the world collapsed. The Dow Jones Industrial Average fell 22.6%, a larger percentage loss than any other single day in the index’s history.

The crash was not limited to the United States. Major markets in Hong Kong, the United Kingdom, Australia, Canada, and elsewhere also suffered steep declines. Its global reach helped turn the date into one of the best-known names in financial history.

Black Monday is sometimes confused with Black Tuesday, the climactic day of the 1929 Wall Street Crash, or Black Thursday, the first major panic day in October 1929. The shared naming convention refers to different crashes separated by nearly six decades.