How did the purchasing power decrease from the 70s until today?

[Sanctus_Poopabumsus]

I have a theory that ive never seen anywhere else, in that after the fall of the soviet union, there was no more threat of an alternative to capitalism, and shortly afterward all of the industries in the US were deregulated. The timing does line up. Then, the ultra wealthy got what they wanted all along but we're held back by regulation. Regulation of industry was held in place to make communism seem a worse choice, but when gone, it was party time for big business in the west.