Although this was not the sole reason for the Great Depression, it did speed up the rate at which the economy collapsed, of which it was also a symptom. Stock prices began to fall quickly and millions of stocks were traded on Black Thursday, and the real fall began on October 29th. After this day, stock prices had nowhere to go but up, so there was considerable recovery during succeeding weeks. Overall, however, prices continued to drop as the United States slumped into the Great Depression, and by 1932 stocks were worth only about 20 percent of their value in the summer of 1929.