Hanna Rosin debunks the meme that “women only get paid 77 cents for every dollar earned by men doing the same job”:
The official Bureau of Labor Department statistics show that the median earnings of full-time female workers is 77 percent of the median earnings of full-time male workers. But that is very different than “77 cents on the dollar for doing the same work as men.” The latter gives the impression that a man and a woman standing next to each other doing the same job for the same number of hours get paid different salaries. That’s not at all the case. “Full time” officially means 35 hours, but men work more hours than women. That’s the first problem: We could be comparing men working 40 hours to women working 35.
How to get a more accurate measure? First, instead of comparing annual wages, start by comparing average weekly wages. This is considered a slightly more accurate measure because it eliminates variables like time off during the year or annual bonuses (and yes, men get higher bonuses, but let’s shelve that for a moment in our quest for a pure wage gap number). By this measure, women earn 81 percent of what men earn, although it varies widely by race. African-American women, for example, earn 94 percent of what African-American men earn in a typical week. Then, when you restrict the comparison to men and women working 40 hours a week, the gap narrows to 87 percent.
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Goldin and Lawrence Katz have done about as close to an apples-to-apples comparison of men’s and women’s wages as exists. (They talk about it here in a Freakonomics discussion.) They tracked male and female MBAs graduating from the University of Chicago from 1990 to 2006. First they controlled for previous job experience, GPA, chosen profession, business-school course and job title. Right out of school, they found only a tiny differential in salary between men and women, which might be because of a little bit of lingering discrimination or because women are worse at negotiating starting salaries. But 10 to 15 years later, the gap widens to 40 percent, almost all of which is due to career interruptions and fewer hours. The gap is even wider for women business school graduates who marry very high earners. (Note: Never marry a rich man).
I’ve posted similar articles on this topic before: August, 2012, June 2012, and July 2010.