Black Tuesday, one of the defining trading days of the 1929 Wall Street crash, occurred on October 29, 1929.
On that day, roughly 16 million shares changed hands on the New York Stock Exchange, overwhelming the trading system of the era. The Dow Jones Industrial Average fell sharply, following heavy selling on Black Thursday, October 24, and Black Monday, October 28. The market continued declining after Black Tuesday and did not reach its ultimate low until 1932.
The crash followed years of speculative buying, widespread use of borrowed money, and rapid expansion in stock prices during the 1920s. It was an important trigger and symbol of the Great Depression, although the depression also involved banking failures, falling demand, deflation, and international economic problems.
Black Tuesday is not the same as Black Thursday, the first major panic day in the October 1929 sequence. Both dates are associated with the same crash, but October 29 is the standard answer to the Black Tuesday question.