things that are directly calculable --- such as career selection, and hours worked. The balance is due to a myriad of factors which are not directly calculable but can reasonably be concluded to be heavily tied to the two factors listed above -- such as lower hour worked leading to smaller raises fewer promotions -- particularly in higher skill/higher pay demanding jobs where someone working 60-70 hours per week is just going to get more accomplished on average than someone working 9-5 and making a beeline out the door at 5:00 to pick up the kids from daycare. It's not "fair" maybe that those duties fall disproportionately on the mother vs. the father, but that's a husband / wife discussion... not something the company should be expected to normalize for.

You also have an indirect impact of career selection. A high proportion of executives have engineering degrees (roughly 1/3 of CEOs). I look at the "C" suite for my company, and everyone except our CFO is an engineer (and with the exception of my current CFO, every other CFO i've worked for was an undergrad engineer). Yet less than 20% of engineers are women.

As I posted below, I believe the glass ceiling is real and there is a bit of a subconscious (or in some cases conscious) "old boy" network at work where current executives are drawn to mentor younger workers that remind them of themselves when they were earlier in their career. Naturally, since most executives are male, the young workers that "remind them of themselves", tend to also be male. So you get a bit of a self perpetuating cycle. But I also believe that factor (which is a big factor) is being offset by diverse talent programs at most major companies. We take it VERY seriously at my company (and really every company I've ever worked for), where high potential women and minority employees are identified and specifically tracked for advancement.

And I promise you that no major company allows women to be paid less for the same job with the same qualifications as a male counterpart.