The Dow Jones Industrial Average fell 22.6% on October 19, 1987, the largest single-day percentage decline in its history. The date became known worldwide as Black Monday.
The fall occurred in a rapidly internationalizing market sell-off. Stock prices had risen strongly before the crash, while investors worried about interest rates, trade tensions, and economic conditions. Computerized portfolio-insurance strategies and other automated selling mechanisms amplified the downward move by generating more sell orders as prices declined.
The crash spread across markets in Asia, Europe, and North America, but it did not produce a depression comparable to the 1930s. The Dow eventually recovered, helped in part by Federal Reserve action and changes in market structure. The figure is often confused with the 1929 crash: October 28, 1929, saw a Dow fall of about 12.8%, while 22.6% remains the 1987 record.