In various discussions, this 5 to 1 ratio shows up quite a bit, either as a ratio of casualties or a ratio of required advantage to defeat a German force. Sometimes it is more, sometimes it is less, but 5 being a nice round number it is repeated quite often to illustrate the claim that the Allies only conquered Germany with the might of industry and "human waves", despite superior German technology and soldiers.
However, these claims seldom hold any actual numbers or evidence behind them. Let us briefly explore the feasibility of this claim.
Despite being a much larger country, the Soviet Union did not possess a proportionally larger population. The German census in 1939 counted a population of about 79 million. The Soviet census in 1937 counted about 162 million people. Assuming that both countries could raise similar proportions of fighting men, it becomes quite clear that a 5:1 casualty ratio is simply not possible here, as the Wehrmacht could simply kill literally every single Soviet citizen with ease. Glantz's essay The Soviet-German War 1941-1945: Myths and Realities gives some more numbers:
|Date||German forces in theater||Red Army forces in theater|
Edit: it appears that many commenters believe that Glantz's numbers do not accurately represent the amount of Red Army forces and were purposefully chosen to minimize the number of troops available. Livejournal user buckina_new compiled a nice chart using Krivosheev's data about the number of men in the Red Army every quarter.