The US equity market plunged dramatically in 1929 triggering the Depression. From the peak of 1929 to the bottom reached in 1932, millions were unemployed and untold misery was brought upon the general population.After FDR was inaugurated as the 32nd President of the United States the economy slowly started to recover.
The chart below shows the returns of the Dow Jones Index from 1929 through 1940:
Click to enlarge
Source: Stock Markets during the second World War, Investment Office