▁mak ers ▁have ▁fewer ▁in cent ives ▁to ▁strength en ▁un ions ▁or ▁otherwise ▁equal ize ▁economic ▁re wards ." ▁Un ions ▁were ▁a ▁bal ancing ▁force , ▁helping ▁ensure ▁w ages ▁kept ▁up ▁with ▁product ivity ▁and ▁that ▁neither ▁execut ives ▁nor ▁share hold ers ▁were ▁und uly ▁reward ed . ▁Further , ▁soci etal ▁norm s ▁placed ▁constraints ▁on ▁executive ▁pay . ▁This ▁changed ▁as ▁union ▁power ▁decl ined ▁( the ▁share ▁of ▁union ized ▁workers ▁fell ▁significantly ▁during ▁the ▁Great ▁D iver gence , ▁from ▁over ▁ 3 0 % ▁to ▁around ▁ 1 2 %) ▁and ▁CE O ▁pay ▁sky ro cket ed ▁( ris ing ▁from ▁around ▁ 4 0 ▁times ▁the ▁average ▁workers ▁pay ▁in ▁the ▁ 1 9 7 0 s ▁to ▁over ▁ 3 5 0 ▁times ▁in ▁the ▁early ▁ 2 0 0 0 s ). ▁A ▁ 2 0 1 5 ▁report ▁by ▁the ▁International ▁Mon et ary ▁Fund ▁also ▁attributes ▁the ▁decl ine ▁of ▁labor ' s ▁share ▁of ▁G DP ▁to ▁de union ization , ▁not ing ▁the ▁tr end ▁" necess arily ▁increases ▁the ▁income ▁share ▁of ▁corpor ate ▁man agers ' ▁pay ▁and ▁share holder ▁returns ▁... ▁Moreover , ▁we aker ▁un ions ▁can ▁reduce ▁workers ' ▁influence ▁on ▁corpor ate ▁dec isions ▁that ▁benefit ▁top ▁ear ners , ▁such ▁as ▁the ▁size ▁and ▁structure ▁of ▁top ▁executive ▁compens ation ." ▁ ▁Still ▁other ▁research ers ▁think ▁it ▁is ▁the ▁labor ▁movement ' s ▁loss ▁of ▁national ▁political ▁power