Which U.S. index suffered the famous 508-point loss on Black Monday in 1987?

The Dow Jones Industrial Average suffered the famous 508-point loss on Black Monday in 1987.

On 19 October 1987, the Dow dropped from 2,246.74 to 1,738.74, a fall of 22.6 percent. The index tracks 30 prominent U.S. companies, so its historic loss became the most widely quoted measure of that day’s market panic.

The S&P 500 and Nasdaq Composite also declined sharply, but neither is the source of the commonly cited 508-point figure. The numerical size of a point loss depends on an index’s level and construction, so percentage comparisons are more meaningful across different eras.

After the crash, U.S. exchanges introduced circuit breakers and other safeguards designed to slow extreme declines. These mechanisms can pause trading when prices move beyond specified thresholds, giving investors time to assess rapidly changing conditions.