▁has ▁concentr ated ▁in ▁mon opol ies ▁and ▁o lig opol ies ▁that ▁enable ▁unusual ▁amounts ▁of ▁income ▁(" r ents ") ▁to ▁be ▁transferred ▁from ▁the ▁many ▁consum ers ▁to ▁relatively ▁few ▁own ers . ▁This ▁hypothesis ▁is ▁consistent ▁with ▁higher ▁corpor ate ▁prof its ▁without ▁a ▁comm ens ur ate ▁rise ▁in ▁invest ment , ▁as ▁fir ms ▁facing ▁less ▁competition ▁choose ▁to ▁pass ▁a ▁greater ▁share ▁of ▁their ▁prof its ▁to ▁share hold ers ▁( such ▁as ▁through ▁share ▁buy back s ▁and ▁divid ends ) ▁rather ▁than ▁re - in vest ▁in ▁the ▁business ▁to ▁w ard ▁off ▁compet itors . ▁▁ ▁One ▁cause ▁of ▁this ▁concentration ▁of ▁market ▁power ▁was ▁the ▁right ward ▁shift ▁in ▁American ▁politics ▁toward ▁more ▁conserv ative ▁policies ▁since ▁ 1 9 8 0 , ▁as ▁politics ▁plays ▁a ▁big ▁role ▁in ▁how ▁market ▁power ▁can ▁be ▁exerc ised . ▁Pol ic ies ▁that ▁removed ▁bar riers ▁to ▁mon opol y ▁and ▁o lig opol y ▁included ▁anti - union ▁laws , ▁reduced ▁anti - tr ust ▁activity , ▁der eg ulation ▁( or ▁failure ▁to ▁reg ulate ) ▁non - de pository ▁bank ing , ▁contract ▁laws ▁that ▁fav ored ▁credit ors ▁over ▁deb t ors , ▁etc . ▁Further , ▁rising ▁wealth ▁concentration ▁can ▁be ▁used ▁to ▁purchase ▁political ▁influence , ▁creating ▁a ▁feedback ▁loop . ▁ ▁Dec line ▁of ▁un ions ▁ ▁The ▁era ▁of ▁inequality ▁growth ▁has ▁coinc ided ▁with ▁a ▁dram atic ▁decl ine ▁in ▁labor ▁union ▁membership ▁from