According to iStrategyLabs, for the past three years 3.3 million teens between the ages of 13 to 17 have left the site, which is decline of 25.3 percent according to the chart above. On the other hand, older users ages 25 and above are increasing their membership. Facebook’s demographics are a lot older now! I’m sensing teens are finding newer outlets. Once the old people move, teens are typically already at the exit signs.