You made the comment that over 13 years we have narrowed the gap by 3%. My contention would be that as women grow in their experience....
I worked as a draftsman in an engineering office. I was paid equivalent to what an entry-level male draftsman would be making. But I was not making the same wage as the design draftsman at the desk next to me, who had 25 years experience over me. My expectation, had I stayed in that career, is that my experience and years of involvement in that craft would have narrowed that gap very quickly, because I had education that he didn't have. I see that as a real proponent for us as females moving forward in the workforce.