see more

DETROIT, MI - JUNE 7: Mary Barra, Chairman and CEO of General Motors, holds a media briefing at the 2016 GM Annual Meeting of Shareholders on June 7, 2016 in Detroit, Michigan. GM stock closed at $29.99 a share on Monday. (Photo by Bill Pugliano/Getty Images)

DETROIT, MI - JUNE 7: Mary Barra, Chairman and CEO of General Motors, holds a media briefing at the 2016 GM Annual Meeting of Shareholders on June 7, 2016 in Detroit, Michigan. GM stock closed at $29.99 a share on Monday. (Photo by Bill Pugliano/Getty Images)