Asignificant cause of the great depression of the 1930's was that

The Great Depression lasted from 1929 to 1939, and was the worst economic downturn in the history of the industrialized world. It began after the stock market crash of October 1929, which sent Wall Street into a panic and wiped out millions of investors. Over the next several years, consumer spending and investment dropped, causing steep declines in industrial output and employment as failing companies laid off workers. By 1933, when the Great Depression reached its lowest point, some 15 million Americans were unemployed and nearly half the country’s banks had failed.