I have read a similar article and I remember the number being between 10% and 15% depending on the quality of vegetation. With good vegetation or supplemental feeding, it is entirely possible to see 20% jumps but I don't think you'll see it every year. 3 - 4 and then 4 - 5 will be your big jumps. I think it also depends on the deer and if his genetics are even capable of puting on the inches.