Though one assumes that there will be many Johns and many Marys, the social norms that influence labor force participation in our country make it likely that while the number of female and male near-retirees that exit the workforce, or rather that reduce their work hours, might be broadly similar, the number of women who reduce their work hours once they have a child is considerably larger than the number of men who will do the same. (See Alberto Alesina, Andrea Ichino, Loukas Karabarbounis on “gender-based taxation and the division of family chores.”) The Pew Research Center reports that mothers are the sole or primary breadwinners in 40 percent of U.S. households with children. One-fourth of these households are headed by single-mothers; 15 percent of these households are households in which a mother earns more than a father. This leaves 60 percent of households with children in which a father earns more than a mother, and as a general rule, second earners already face high effective marginal tax rates. The Affordable Care Act will tend to increase marginal tax rates on second earners, as the value of health insurance subsidies is tied to household income.