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There are a lot of interesting tidbits in the Harvard Crimson's summary of survey results from this year's senior class. Of the 780 graduating seniors who responded (about half the class), 13 percent claim to have had sex in the library during their time in college. Half the male students say they watch porn at least once a week. 15 percent of students have jobs in finance for next year—but only 5 percent say they want to still be in the industry a decade from now.

The most fascinating (and depressing) statistics, though, illustrate the wage gap that exists between male and female students:

Salary differs noticeably between male and female students. Men are much more likely to appear in the highest pay brackets than women: Of the students who expect to earn more than $110,000 in their first year of work, three-quarters are male. Of those who will earn $90,000 to $110,000, men represent nearly two thirds. And those numbers come from a pool of respondents which included more women than men, suggesting that the true tallies are in fact slightly more weighted in men's favor.

The difference in industries chosen by male and female students partially accounts for the difference in pay. Men enter finance, consulting, and technology at higher rates than women, while more women pursue education, media, and health after college.

But industry alone does not explain the wage gap. Among students entering finance, men are still nearly four times as likely to earn more than $110,000 per year, and three times as likely to earn $90,000 to $110,000. Admittedly, the sample sizes are small. But the same holds true in consulting. And in technology and engineering, 79 percent of men expect to make more than $90,000, compared to just 44 percent of women in the same field.

Notice how the wage gap also exists within industries—that men and women from the same prestigious college entering the same prestigious fields earn, on average, different amounts. This is important in understanding the conversation around the overall wage gap in America, where women earn about three quarters of what men do. Often, people try to explain away that gap by saying women choose fields that pay less. That's true, in part. But as the Harvard class shows, even women who pick careers in high-earning fields like finance and tech can often make less than their male peers. There are any number of theories to explain this: outright discrimination; a gap in negotiating skills between men and women; perhaps a male tendency to exaggerate his salary in a survey (or a female tendency to round hers down). The one explanation that does not work, though, is to attribute the gap mainly to women's career choices.