ribute ▁income ▁from ▁higher ▁income ▁to ▁lower ▁income ▁households ▁relatively ▁less ▁than ▁other ▁developed ▁countries . ▁Journal ist ▁Tim othy ▁No ah ▁summar ized ▁the ▁results ▁of ▁several ▁studies ▁his ▁ 2 0 1 2 ▁book ▁The ▁Great ▁D iver gence : ▁Econom ists ▁P ik et ty ▁and ▁S ae z ▁reported ▁in ▁ 2 0 0 7 , ▁that ▁U . S . ▁tax es ▁on ▁the ▁rich ▁had ▁decl ined ▁over ▁the ▁ 1 9 7 9 – 2 0 0 4 ▁period , ▁contrib uting ▁to ▁increasing ▁after - tax ▁income ▁inequality . ▁While ▁dram atic ▁redu ctions ▁in ▁the ▁top ▁marg inal ▁income ▁tax ▁rate ▁contributed ▁somewhat ▁to ▁w ors ening ▁inequality , ▁other ▁changes ▁to ▁the ▁tax ▁code ▁( e . g ., ▁corpor ate , ▁capital ▁g ains , ▁estate , ▁and ▁gift ▁tax es ) ▁had ▁more ▁significant ▁impact . ▁Consider ing ▁all ▁federal ▁tax es , ▁including ▁the ▁pay roll ▁tax , ▁the ▁effective ▁tax ▁rate ▁on ▁the ▁top ▁ 0 . 0 1 % ▁fell ▁dram atically , ▁from ▁ 5 9 . 3 % ▁in ▁ 1 9 7 9 ▁to ▁ 3 4 . 7 % ▁in ▁ 2 0 0 4 . ▁C BO ▁reported ▁an ▁effective ▁tax ▁rate ▁decl ine ▁from ▁ 4 2 . 9 % ▁in ▁ 1 9 7 9 ▁to ▁ 3 2 . 3 % ▁in ▁ 2 0 0 4 ▁for ▁the ▁top ▁ 0 . 0 1 %, ▁using ▁a ▁different ▁income