Fewer women than men with the name 'John' run big firms

FEWER large companies are run by women than by men named John, a sure indicator that the glass ceiling remains firmly in place in corporate America.

Among chief executives of S&P 1500 firms, for each woman, there are four men named John, Robert, William or James. We're calling this ratio the Glass Ceiling Index, and an index value above one means that Jims, Bobs, Jacks and Bills - combined - outnumber the total number of women, including every women's name, from Abby to Zara. Thus we score chief executive officers of large firms as having an index score of 4.0.

Our Glass Ceiling Index is inspired by a recent Ernst & Young report, which computed analogous numbers for board directors. That report yielded an index score of 1.03 for directors, meaning that for every one woman, there were 1.03 Jameses, Roberts, Johns and Williams - combined - serving on the boards of S&P 1500 companies.