Lots! The bottom line is, they stop growing when you kill them.
We started QDM in 1991, way before it was even popular around the area. I was still pretty young and had a little blood in my eye yet so dad told me as long as it's bigger than anything you've already shot, go ahead. That way every couple years atleast I was able to kill a buck. Trust me, passing the little ones WILL pay off eventually.