I’ve gone to quite a few butchers in the northern half of New Jersey and a couple in Pennsylvania and i’ve always gotten back 25 to 30% of the deers field dressed weight in boneless meat. The more silver skin the butcher trims off the meat the less you are going to get back. If you do a terrible job field dressing that is also going to effect how much you are going to get back. I can’t tell you how many deer I see at the butcher shop that the guys do an absolutely horrible job of field dressing.
Shot placement also plays a big role. My buddy goes to a butcher in Monmouth County and he said there’s a sign that says you get back 20 to 25% of your deers hanging weight in boneless meat. I’ve also noticed that a lot of guys I hunt with and guys I run into at the butcher shop always think that their deer is way bigger than it really is.