More on Gender Pay Inequity and Loss of Income for Staying At Home

https://www.nbcnews.com/better/business/gender-wage-gap-widens-43-percent-age-45-ncna772411
But the pay gap also widens when men and women switch jobs: Men get a bigger pay bump when they join a new company, and are somewhat more likely to make the move. Even though women changed jobs almost as frequently as men, the pay bump was especially small for women who were married.
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Goldin says that the difference for college-educated workers in large part comes down to women choosing flexibility over higher pay, something she calls “choice under constraint.” These women might want to stay in their job but not come in Friday mornings, for example, but because that is not an option for them, they’ll take a lower paying job with more flexibility.

http://www.workingmother.com/this-calculator-tells-you-exactly-how-much-money-you-lose-when-you-stay-home-with-your-kids?src=soc&dom=fb

A 26-year-old woman earning $100,000 stands to lose more than a million over her lifetime if she stays home for five years.
In addition to the wages moms and dads lose when they’re not working, they also lose the chance to receive raises and to sock away retirement savings. And because the effects are cumulative, they add up over time to a whole lot of money.