The General Motors Company, also known as GM, is a United States-based automaker with its headquarters in Detroit, Michigan. By sales, GM ranked as the largest U.S. automaker and the world's second-largest for 2008, having the third-highest 2008 global revenues among automakers on the Fortune Global 500. GM previously led in global sales for 77 consecutive years (1931 to 2008), longer than any other automaker. The company was founded on September 16, 1908, in Flint, Michigan, as a holding company for Buick.