I'd have to say that the average Age is most likely a wild number. You'd be surprised at the amount of adults that like to play too.
For example, I'm in my 40's, my wife who plays is in her 30's. My oldest daughter and her husband play, and they are in their 20's and I have a young son who is not quite a teen yet that likes to play too!
So where is the average there? hehehe. Who plays the most out of the group I just mentioned?
Me and my wife!
Arrrrr!
