In a comment to my last post, Phllip Kerman notes that plenty of “normal aged” people are using Facebook. It caused me to wonder, what age is normal? I rather think that any age where you are healthy of mind and body is normal, but perhaps he meant the age with the largest number of people. In the U.S. in 2000 that would be 40-49 year olds, if we look at the general population. (That’s a actually a little older than me.)
It may be more relevant to look at the online population. Although facebook does allow you to register if you were born last year, the babies are toddlers are an unlikely audience. In any case, the stats I found were for online adults. If you are online and over 18, you are most likely to be 18-29 years old. If I were to find a more finely grained data of for online population, my guess is that facebook targetted the most populous demographic for online activity with its initial offering for the college kids.