I find that hard to believe, considering the Korean war started June 25th, 1950 and ended July 27, 1953. I had many friends who graduated from about 1955 through 1959 go in and then serve in Vietnam (I graduated in 1958.) Without doing any research on breakdown, the US was sending men to Vietnam from about 1960 on, as I recall.
I guess I'll have to go and dig around in the numbers. Now you did it, LOL!