When I was a teenager, I once compared with a couple of cousins of mine. They were brothers, one a year older than me, one a year younger. the older one was just a little over 10" which is an inch bigger than me, the younger was 8" which is an inch smaller than me. If that wasn't wierd enough, the younger ones was as if it was an exact replica of mine but just an inch smaller. At that time we were not into taking circum.