I'll go with the early 80s as well (specifically the early 80s). I could go into just about any major town, find the local game store and go in and find out when they were running games. In certain areas you could walk in any night of the week and find an RPG, and often several on weekends (my FLGS was like this).
Today the game stores are disappearing (although it seems more slowly than they were as early as a year ago). If you go in there are card games and miniature games and the RPG is a rarity. RPGs are moving back to the thing you do in the privacy of your own home, away from the public.
On the positive side, if you are willing and comfortable playing online, this is the best time to find an online game. The tools are becoming sufficient for a quality online game (even if it doesn't match up to a tabletop, face-to-face game). You can find players potentially all over the world, even for the most niche games.
Still, it seems to me that gaming community is becoming more "inbred." A much higher percentage of the roleplayers are long time gamers or the children (nephews, nieces, grandchildren) of longtime gamers. I could be wrong, but doubt anyone has any hard statistics on this, outside of WotC.