After reading all of the theories on what is the most significant factor in increased hunter success in Wisconsin I was surprised to not see what I think is the main 1. MUCH longer hunting seasons. I tried finding info on how long the deer seasons were in the 60' s and while not finding specific dates it appeared they were only a few weeks long for ALL hunters. As time went on and archery season became its own season I think you would find your first significant jump. I also think archery seasons being earlier in the year when deer are easier to pattern would have been a huge advantage, as well as hunting the rut the " prime time" for bagging a buck.

I' m not from Wisconsin and finding deer season data by hunting methods for 20+ years ago isn' t easy on the web, but I do know that from the 70' s to 2003 in the Northeast hunting seasons are months longer than they used to be. I think the combination of higher deer populations plus much longer hunting seasons plus technological advances is the reason for higher success rates ..... in that order I would think.