Over the past 40 years, the labor force participation of women with children under 18 has grown from 47 percent in 1975 to 70 percent today. [1975: Families and Work, 2015: Department of Labor] Raising a child is now the single greatest expense for most American families -- even exceeding the cost of housing in much of the country. [National Affairs, Winter, 2015] Almost two-thirds (64 percent) of mothers with children under 6 are working outside of the home [Bureau of Labor Statistics] Today's workforce includes 73.5 million women representing 47 percent of the entire US labor force. [Department of Labor] Over 24 million of those women have children under age 18; almost 10 million of them have children under age 6. [Bureau of Labor Statistics] Women are the primary breadwinners in 40 percent of American households with children under the age of 18, but hold 62 percent of minimum wage jobs. [Pew Social Trends; National Affairs Winter, 2015]