I saw an academic presentation of some research that found evidence that, after controlling for a number of factors like hours worked per week, dangerous jobs, and dirty jobs, that women got paid more than men. Pay was not just a dollar-per-hour thing. In his data, if someone worked 44 hours per week or more, he or she got paid a lot more. By far, men worked longer hours and got more salary. Men tended to do more jobs where they were exposed to the elements and where the work was dangerous or unpleasant (construction, garbage collection) which paid a premium for these unfavorable factors. Women tend to gravitate toward some of the lower-paying jobs like teaching and social work. (I'd imagine nursing is an exception.)
There are also more women in college these days.
Pouring money into raising women's wages and getting more women in college may be putting the money in the wrong place.