The average woman who had a full-time, year-round job in 2015 made just 80 percent of what a man did, according to the latest data from the Census Bureau. That’s up from last year’s 79 percent, but the increase is not statistically significant. The wage gap hasn’t closed significantly since 2007.

In 2015, men made $51,212 at the median, compared to $40,742 for women, a $10,470 difference. Both experienced an increase in income—1.5 percent for men and 2.7 percent for women—the first significant raise since 2009.

There are a number of factors that go into the gender wage gap. About 20 percent of it is due to the fact that women often end up in jobs and industries that pay less. Occupations with large numbers of women pay about 83 percent as those with large numbers of men. It’s not just that women choose to be in lower paid work; when a large number of women start to enter a job that was previously held by men, the pay drops.

Another portion of the gap can be explained by the fact that women tend to interrupt their careers or cut back on their hours. They are much more likely than men to do this to care for family members, work that still falls mostly to them. Some may have little choice given how few supports, like paid family leave and affordable child care, the country offers them.

But there is a sizable percentage of the gap between women’s and men’s earnings that can’t be explained by various factors—in one comprehensive study, about half of it. Women make less than men in every industry and in virtually every occupation. Even women with the exact same jobs as men earn less than them.

Education can’t close the gap, as female college graduates make less in their first jobs than male ones even when they have the same grades, majors, and other credentials, and women make less than men at every educational level.

There is evidence, however, that women and their work are justundervalued.

This article was originally posted at Thinkprogress.org on September 13, 2016. Reprinted with permission.

Bryce Covert  is the Economic Policy Editor for ThinkProgress. Her writing has appeared in the New York Times, The New York Daily News, New York Magazine, Slate, The New Republic, and others. She has appeared on ABC, CBS, MSNBC, and other outlets.