PR UK You cant even say the US is close, they have a popualtion of just over 300 million. Person-for-person does the US have 5x as many champions today as the UK? Does the US have 75x the amount of champions that PR has, as thats what they would need to have to have a better people-to-champions ration ie P4P.
I was alluding to the fact that somebody has to decide who the champs are and how you become a champ, who gets what fights and so on and so forth. This is what the federations do, among other stuff. So, imagine a Federation or Organization (like the Ring) or whatever you wanna call it, is run mainly by Russians. Don't you think there is a good chance they would be inclined to give Russian boxers more shots at titles than other nationalities? Get the drift? Therefore I don't believe the sheer numbers that answer your original question holds much information content. Or put plainly: There is more to the numbers than meets the eye.