All I can do is guess, but I would guess him as a 3 year old. He certainly does look like a buck that could explode in future years though.
I am convinced though that not every buck "blows up" with each successive year of growth. Sure, I think all bucks get bigger, antlers and body, with age, but some deer have a "pig" like build and some deer have a slight build IMO. Same with antlers, some racks will gain 20"-30" a year, some seem to be almost identical year to year.
We have watched enough deer on our farm for enough years now to get a pretty decent sense of how things go with specific bucks year to year that leads me to these thoughts. I guess some guys will be grow into linemen and some guys will be defensive backs. :grin: