I’d guess > 80% are between 27 and 32. I’d put my personal cuttoff for full-time MBA entry at 32. Once you’re in your mid-thirties hopefully you have a solid career going and you want to continue down that path. An executive or part-time MBA program may be a better option. I think full-time MBA programs have a high percentage of career changers. I’d love to go to Harvard for my MBA. However, at 31 with a good career that I can see a long future in, it wouldn’t be worth taking 1.5 years off when I could instead go to Wharton’s executive program (big assumptions saying I could get into either, but this is hypothetical).