[Kind of off-topic] I'm guessing you mean by 'than Vietnam', 'than Americans died in the Vietnam war"? (Well I think so. Apologies if not.) That's a pretty macabre unit. Can you imagine how a Vietnamese person would feel reading that? Maybe in Vietnam they say 'More people die from [something] every year than America' - meaning what they call the American War[0]. Wouldn't that sound super-weird. That's something like how what you said sounds to me. Only for them it would mean 1-3 million.
[0] or the Resistance War Against America.
edit: Downvoter, care to explain how I can improve my comment? Thanks.