Varies big time from one area to the next. I've seen massive differences on farms just 10 miles apart where age classes were the same but one area consistently produced mammoths & genetic masterpieces (even the deer that were, say, 3 and 155-160") VS the other where over years I never saw anything over 160 with fully mature deer of any age.
On those areas that seem to produce "consistent mammoths" and higher scoring deer per age class on average.... EXAMPLES I've seen pretty consistently "A really good buck" could reasonably do 120" as a 2, 140-145" as a 3, 170-175 as a 4, 180-190" 5 and I'd say most those that live to 6 and beyond (the very lucky bucks with excellent gens) getting close to 2 or maybe passing it. It's rare but I'd say "really good genetic bucks" are "reasonably common" but most get killed at 2, 3 or MAYBE 4, especially if really high pressure, lots of shotgun pushers, etc. Getting them mature is harder than finding those really good deer. Good areas always have poor & average deer but getting the great ones to maturity sure is great. I've seen some rare cases with 45-50" jumps in a year.