The Dow Jones Industrial Stock Index had continued its upward move for weeks, and coupled with heightened speculative activities, it gave an illusion that the bull market of 1928 to 1929 would last forever. On October 29, 1929, also known as Black Tuesday, stock prices on Wall Street collapsed. The events in the United States added to a worldwide depression, later called the Great Depression, that put millions of people out of work around the world throughout the 1930s.