"Historically it's one of the most important parts of the period of World War II in France,the roundup - the rafle du Vel dHiv - is a symbol of collaboration between the French police and the German occupying authorities."

VOA: standard.2010.04.10

That has moved around a lot, but it got almost up to 60% in the post World War II period and now it's down to less than a third.

计算所得的百分率变动很大,二战后,它一度达到将近60%,现在又降到不到三分之一

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