My birthday was on Sunday.  Facebook will tell you how many people have posted on your timeline for your birthday.  I started looking back at the history of post to my timeline on my birthday, and it made me curious.  Could I predict how many friends would post to my timeline this year?

I specifically looked for the post that said something like this:

I found data for 2007 – 2014, and created this graph.

Clearly, there were some outliers, so I removed them.

That data sure did look linear, so I added the linear regression.

Based on the regression (look at that r^2), I predicted that 53 friends would post to my timeline for my birthday 2015.

And the official Facebook results:

I would say I have a pretty good model.  If this trend continues, I am predicting 59 friends will post to my timeline for my birthday 2016.