Rachel West and Rebecca Vallas of the Center for American Progress write about the serious effects of income inequality on the Social Security trust funds. Because of the $127,200 cap on wages covered by the FICA tax, rising income inequality a greater and greater portion of income is escaping FICA. It's not like those with incomes over $127,200 a year are struggling. That's the group receiving the vast majority of income gains. If, instead of a flat cap, the FICA cap had been set since 1983 so that 90% of wages are covered, the Social Security trust funds would be $1.3 trillion higher now.