The "Glass Ceiling" Cracketh
What's notable about the study is that it apparently took multiple variables into account --such as age, educational background and experience. In the aggregate, there's no doubt that women still earn less than men; that's attributable, however, to the fact that many of them leave the business world compared to men before they reach the top levels of seniority.
For those who do hang in there, it seems their perseverance is richly rewarded.