Using just "recent" data would probably show zip, as the changes are over generational time. But "cause and effect" are obvious.......lifestyles that promote more total exercise are in better shape overall.
As to where the data is, I don't know and don't much care....this is historical information I read about years ago...maybe even as far back as when I was in college (late 1960's, early 1970's). In those days, it would have been on paper. But it was quoting government data, so it can probably be found online.
"In the USA other than Manhattan and San Francisco I dont even see anecdotal evidence that is correct."
Perhaps because you haven't looked. But I'm certainly not going to do homework for you, as the subject is of minimal interest to me. I was simply sharing info that I knew about.
Sure.