[thomasz]

Despite all its shortcomings, the USSR did pretty well in areas they really cared about, like tank production. And it’s very difficult to compare the value of a t80 with the value of a m1, especially when there was little trade between both blocks. The USSR sold energy to Western Europe in order to get dollars which were then used to buy grain from the US. And that was just about it.

Your problem isn’t with PPP but with the Soviet societal tendency to falsify reports on absolutely every level and with the inherent incomparability between planned and market economies.