The document discusses the business cycle in the United States in the early 20th century. It summarizes that the Great Depression in the 1930s was caused by inequality in wealth distribution and speculation in the stock market in the 1920s. As wages did not increase alongside production, demand slowed and unemployment rose to 25% of the population. The economy eventually recovered during World War 2 as the U.S. supplied arms to countries at war, enlisting over 10 million people into the military and factories.