Facebook thinks they can know a lot about you based on your profile photo. Not the actual picture per se, but the metrics behind it. Such as, how often you change your profile photo. The percentage of all your photos that have been used as profile photos. And how many profile photos you have, in total.
Take a minute and think of those numbers. Now, based on the numbers that Facebook’s Director of Analytics has dug up, see whether they have you pegged.
In general, 1 in 10 photos on Facebook is a profile shot. Women, on average, change their Facebook profile photo every 2 weeks. Men every 3 weeks. The average Facebook user has 26 profile photos and growing.