Black Tuesday occurred on October 29, 1929, when the New York Stock Exchange suffered an unprecedented wave of selling. About 16 million shares changed hands, a record that stood for decades, and the Dow Jones Industrial Average fell approximately 12%. The session is widely treated as the climactic day of the Wall Street Crash of 1929.
The crash followed years of rapid share-price rises, widespread speculation, and purchases made with borrowed money. The market had already fallen sharply on Black Thursday, October 24, and Black Monday, October 28. Panic intensified as investors rushed to sell while buyers disappeared.
Black Tuesday did not by itself cause the entire Great Depression. The collapse damaged confidence, reduced household wealth, weakened banks and businesses, and contributed to a prolonged economic downturn. The Dow continued falling after October 29 and reached its bear-market low in July 1932.
A common mix-up is calling October 24 the sole crash date. That day was the first major panic session, but October 29 is the date attached to the name Black Tuesday.