The reason for this is not the in general not existing difference in maturity between a 23 year old, like me, and a 27 year old, but rather, as I believe, the time when Civ I came out. Most people under the age of 25 weren't really in an age when parents would allow them to play or didn't even have a PC back then.What's interesting about the histogram is it shows a higher incidence of 25-30 yr/old playing civ then 20-25. Much higher in fact. I don't know if it's because these young kids now 'adays don't have the paitence for turn-based strategy, or the ceontect in civ appeals more to a mature audience. I think one thing we all need to do is encourage more female gaming!