Although the tenure of male chief executives at Fortune 1000 companies is
shortening, it is not as short as the average tenure for females. A recent
study shows that the average male CEO of a large publicly traded company holds his job for 8.2 years, while women stay 4.8 years. Some analysts attribute the shorter tenures for women to a clear pattern of more women
than men taking over the leadership of companies that are struggling and in need of a turnaround. Still, there are so few women in CEO positions that it is difficult to draw conclusions.
See "Above the glass ceiling the footing is fragile", Kimberly Blanton, The Boston Globe, February 17, 2005