I was also looking for a mention of such a statistic.
I have been vegetarian for 2+ years, occasionally cheat with sea food, but the idea of eating animal flesh grosses me out and i don't think I'll ever turn back.
I've been vegetarian for 10+ years, "lapsed" for a few months after my life was turned upside down by a series of events but quickly just went back to vegetarianism because it was easier for me. Once you get into a routine, you'll probably stick with it.