In the U.S., the average educated working woman earns %21 less than what an average educated working man earns. This means $4 for women for every $5 for men.
If you look closer to the situation, black women earns 60 cents for every dollar average man makes and Latinas are just paid only 55 cents. Even the gap between these salaries are large, they were larger in the early forties. In those times average female college graduate woman earns %45 less then a man.
According to researches, men see higher salaries sooner even men and women work at the same company. And there is more, as men grow older they move on higher paying positions and firms more often than women do.