How many people are 'straight edge',which means you do not smoke,drink or do drugs,that's straight edge?

Two of my closest friends are like that.  They never drink or do anything of the sorts.  I'm very selective on my friends but seeing as I know two 'straight edge' people I'm guessing there are many like them.  They're really great at parties.  They drive me home and remind me where I was and what I did... Oh, and tell me where I left my car.

I know a guy named Sean who doesn't do anything anymore, but he did in the past..... But these days he will have a beer and glass of champagne on New Years, but the rest of the year he may as well be Amish.