the previous 4 years, whereas Helton inherited a squad that went 39-18 in the 4.25 years before he took over. There also weren't any UNLVs on the schedule back in McKay's day.
Records today are NOT comparable to records back then. They just aren't. The game has changed a little bit in the nearly 60 years that passed since McKay's first years. Shocking I know, but context matters.