Black Tuesday, the second famous panic day of the 1929 U.S. stock-market crash, occurred on October 29, 1929.
On that Tuesday, investors traded roughly 16 million shares on the New York Stock Exchange, then an extraordinary volume. The Dow Jones Industrial Average fell about 12%, intensifying the collapse that had begun the previous week.
Black Thursday, October 24, had produced the first major wave of panic, while Black Monday and Black Tuesday followed on October 28 and 29. The labels refer to trading days, not to an official government designation.
The crash did not by itself cause the entire Great Depression, but it severely damaged confidence and exposed weaknesses in banking, credit, and industrial production. The Dow did not regain its September 1929 peak until 1954.