Which 1929 crash day saw heavy selling after the Dow Jones Industrial Average fell 12.8%?

Black Monday on October 28, 1929, was the 1929 crash day when the Dow Jones Industrial Average fell 12.8%.

The decline followed a sharp fall on Black Thursday, October 24, and came before the even more famous Black Tuesday, October 29. On Black Monday, selling intensified as investors feared further losses and brokers demanded additional collateral from customers who had bought stocks on margin.

The Dow fell 38.33 points, or 12.82%, on October 28. The next day it dropped another 11.73%, completing the most dramatic phase of the Wall Street Crash. The market’s later decline contributed to the economic contraction known as the Great Depression, although the crash alone did not cause every aspect of that depression.

Black Monday 1929 should not be confused with Black Monday 1987, when the Dow lost 22.6% in a single day. It also differs from Black Tuesday, the 1929 day often most closely associated with the crash.