Women also tend to enter lower-paying fields, even when they have similar educational backgrounds to men. Women with MBAs are more likely to pursue careers in marketing and advertising compared to men, while men are more likely to pursue careers in higher-paying industries like financial services.
"I would say sometimes it's a choice and sometimes it's not," says Frank. "Sometimes that's just where they're getting hired, even if they have been attempting to be hired elsewhere."
According to Nicole Smith, Research Professor and Chief Economist at the Georgetown University Center on Education and the Workforce (CEW), the lower-paying fields that women pursue do account for some of the pay gap, but not all of it.
"We still have women making personal decisions to pursue degrees that pay less," Smith tells CNBC Make It, listing fields such as teaching and nursing as examples of low-paying occupations that women pursue disproportionately. "We still have occupational segregation, which yes, it is a personal decision, but it's also driven by socioeconomic challenges and it is also driven by expectations about what roles women should play in society."
"Occupational segregation" is just one factor that contributes to the current pay gap, says Smith. When the CEW looked at salaries among individuals in the same industries with the same jobs and the exact same level of education, men still earned more. When controlled for factors such as these, Smith and her team found that women still earn about 92 cents for every dollar a man makes.
Anthony P. Carnevale, lead author of Georgetown's report, says that ultimately, the reason highly-educated women experience significant wage gaps is discrimination.
"Women's earnings still lag their exceptional educational progress," he says in a statement. "At the heart of the gender wage gap is discrimination in pay for the same sets of qualifications and experience."
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