Not quite two years. Got the original for B-day in 08. My older daughter and her former boyfriend played at the time. I got a friend of mine into it last year, and he has like three or four 80s already. But he has no kids, is wife works opposite shift and he's been a serious gamer since the days of Commodore 64 and the old original Nintendo system. (Yes we are pretty much first generation gamers. We just never stopped.)
The one thing everybody needs to remember is that I never claimed to be sane!