1 0 ▁tax ▁exp end it ures ▁total led ▁$ 9 0 0 ▁billion . ▁This ▁is ▁a ▁proxy ▁for ▁how ▁much ▁they ▁reduced ▁reven ues ▁or ▁increased ▁the ▁annual ▁budget ▁def ic it . ▁Tax ▁exp end it ures ▁tend ▁to ▁benefit ▁those ▁at ▁the ▁top ▁and ▁bottom ▁of ▁the ▁income ▁distribution , ▁but ▁less ▁so ▁in ▁the ▁middle . ▁ ▁The ▁top ▁ 2 0 % ▁of ▁income ▁ear ners ▁received ▁approximately ▁ 5 0 % ▁of ▁the ▁benefit ▁from ▁them ; ▁the ▁top ▁ 1 % ▁received ▁ 1 7 % ▁of ▁the ▁benefits . ▁ ▁The ▁largest ▁single ▁tax ▁exp end iture ▁was ▁the ▁ex clusion ▁from ▁income ▁of ▁employ er ▁spons ored ▁health ▁ins urance ▁($ 2 5 0 ▁billion ). ▁Pre fer ential ▁tax ▁rates ▁on ▁capital ▁g ains ▁and ▁divid ends ▁were ▁$ 1 6 0 ▁billion ; ▁the ▁top ▁ 1 % ▁received ▁ 6 8 % ▁of ▁the ▁benefit ▁or ▁$ 1 0 9 ▁billion ▁from ▁lower ▁income ▁tax ▁rates ▁on ▁these ▁types ▁of ▁income . ▁ ▁Under standing ▁how ▁each ▁tax ▁exp end iture ▁is ▁distributed ▁across ▁the ▁income ▁spectrum ▁can ▁inform ▁policy ▁choices . ▁ ▁Other ▁causes ▁ ▁Sh ifts ▁in ▁political ▁power ▁Paul ▁K rug man ▁wrote ▁in ▁ 2 0 1 5 ▁that : ▁" E conom ists ▁struggling ▁to ▁make ▁sense ▁of ▁economic ▁polar ization ▁are , ▁increasing ly , ▁talking ▁not ▁about ▁technology ▁but ▁about ▁power ." ▁This ▁market ▁power ▁hypothesis ▁basically ▁as ser ts ▁that ▁market ▁power