This Day in Business History: May 15
- 1918: U.S. airmail begins service between Washington, D.C., Philadelphia and New York.
- 1930: Registered nurse Ellen Church, the first airline stewardess, goes on duty aboard an Oakland-to-Chicago flight operated by Boeing Air Transport, a forerunner of United Airlines.
- 1940: DuPont begins selling its nylon stockings nationally.
- 1963: Weight Watchers is incorporated in New York.
- 2009: General Motors tells about 1,100 dealers their franchises would be terminated.
- 2012: The Beau Sancy diamond, which was passed down by kings and queens in Europe for centuries, sells for $9.57 million at a Sotheby's auction in Geneva.