“It's a pretty strong argument that men and women are not being treated the same,” said Tom White, director of quantitative research for GMI and co-author of the report, which will be released as soon as tomorrow.

He said he and his co-author, Kimberly Gladman, director of research and risk analytics, built the model to test whether women are paid less than men because of factors like age or experience at a company, or simply because they are female.

The study found that, though female CFOs tended to be younger than their male counterparts, there was virtually no difference in their average tenure at a company. The women on average served on a greater number of boards. Female CFOs were rare at the two extremes of market capitalization.

“We tried to turn the question around a little bit,” White said in an interview. “We thought: If men and women are truly being paid the same, then their compensation won't have any predictive value on their gender — it should be irrelevant.”

Using the model, White and Gladman found that, even after accounting for other factors that might affect CFO pay, including market capitalization and chief executive officer pay levels, the average female CFO would earn about $215,000 more if she were male.

“To the extent that this kind of ongoing differential exists and is unexplained, it represents a failure of boards to address an important cultural issue, which is fairness,” said Eleanor Bloxham, CEO of Value Alliance Co., a board advisory firm in Westerville, Ohio.

“There is real discrimination, but nobody wants to deal with it,” Bloxham said in an interview. The people who have made it to these levels don't necessarily want to have that conversation about their gender with the company they work for. They're not necessarily going to raise it.''

Other Factors

She said the problem may be exacerbated by a lack of women on company boards who could advocate for female executives.

The GMI study didn't account for the possibility that female CFOs could have shorter work histories due to being more likely than men to interrupt their careers to bear and care for children, according to the report.

The study also didn't consider the possibility that women might be more likely to move up within a single organization over time. Men may be more likely to switch employers as they move up, a factor that could lead to higher pay.

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