The event officially recognized as the start of the Great Depression in the U.S. is the stock market crash of October 29, 1929, known as Black Tuesday. On this day, the stock market saw its most significant decline, leading to a loss of billions of dollars in stock value and eroding the wealth of many Americans. The crash precipitated a financial crisis that resulted in widespread bank failures, massive unemployment, and a sharp decline in industrial production. This event marked the beginning of a decade-long economic downturn, affecting millions and resulting in significant changes in economic policies, leading to programs such as the New Deal.