Chalk this up to another instance where a girl just can't win.

You know that stubborn pay gap between the sexes? (In big firms, women earn 90 to 94 percent of what men earn in the same position, according to the National Association of Women Lawyers.) Well, the gap might be so entrenched that measures aimed at eradicating it aren't helping, and, in some cases, make it worse.

That's the cheerful finding described in an article in Harvard Business Review by Lydia Frank, a vice president for PayScale, a compensation data company. Based on responses from more than 15,000 job applicants, Frank looked at the effect of the ban on asking job seekers about their salary history. (New York City, Oregon and Massachusetts have adopted the ban, and over 20 states are considering it.)