The DePuy brothers put it at two Germans were worth three western soldiers in combat effectiveness, and one German was worth at least six Soviets.
No doubt that's true, if you are more careful about how you select the data. I am merely taking overall numbers from Matthew White and Wikipedia.
In general, you'd expect an army on offense to lose more than than the defenders as indeed happened during the Winter War in Finland. But this was far from always the case.