I think recruiting was much more strict regarding physical and educational requirements. This kept enlistments down. For example, my father tried to enlist in the AAC in 1937, but was rejected for a stiff knuckle on his left little finger from a whittling accident. A few years later that would not have been a problem. Fortunately, because of the rejection, I and my sisters are here, as he may have been in the P.I. in 1941.