Not a simple answer. Typically deer population goals are set based on the number of deer the land can sustain without degading the habitat. An involved analysis of available food capability vs deer numbers is developed and a sustainable deer population estimate is arrived at. This is monitored and adjusted as necessary over the years. That said, the optimum ratio of bucks to does is 4 to 1 in WI. That's the number of does a buck will breed in a year.