GM's Chevy sales chief in Europe sets September exit DETROIT (Reuters) - General Motors Co (GM.N) said on Friday its Chevrolet and Cadillac sales chief in Europe, where the entire industry has been suffering through a sales slump, is leaving later this year. GM said Susan Docherty, 50, was departing after 27 years with the automaker, effective September 30, to spend more time with her family. A successor was not named. Docherty will remain through September to help with the transition. In a company statement, she said she wanted to "chart a new course" for her career. Docherty assumed her current job in January 2012 and initiated a restructuring of the Chevy business while increasing the brand's market share last year in Europe, GM said. However, Chevy sales in the European Union this year are down 31.5 percent through May, and the brand's market share in the first five months fell to 1.1 percent from 1.5 percent in the same period last year, according to the European car industry association. European car sales plunged last month to their lowest level in 20 years. Before moving to Europe, Docherty served as head of sales in GM's international unit, which includes China. She also was head of U.S. marketing and general manager of Buick-Pontiac-GMC. Reporting by Ben Klayman in Detroit; Additional reporting by Christiaan Hetzner in Frankfurt; Editing by Jeffrey Benkoe