Stock market crash of 1929
In 1929 the Dow Jones Industrial Average (DJIA) declined 90.0% over a duration 34 months. Six successive market crashes comprised this famed crash:
- 1) between September to November 1929 (the DJIA fell 40% in this first phase);
- 2) from April to June 1930;
- 3) from September to December 1930;
- 4) from March to May 1931;
- 5) from July to January 1932;
- 6) from March to July 1932.
A new upswing in DJIA stocks then started immediately, as did a general business recovery.
Business had topped out mildly, a month before the first crash; a gradual mild decline continued to April 1930, then fell sharply into a depression simultaneously with the end of the 1930 stock market rally. The business decline halted in December 1930, stayed level for 6 months, then plunged again in steep economic decline that didn’t lose its downward momentum for a full year, until July 1932. Business improved intermittently thereafter but still remained at depression levels through most of the decade of the 1930s except for a short recovery in 1936–37. 
- Harry Schultz, Bear Market Investment Strategies, Dow Jones-Irwin Co., 2002.