A Startling Discovery

Sorry for the misleading title lol... 

I just discovered something and it's scary and I want advice from the internet, because that always works.

Since I got my title in 2013, my tactics trainer rating graph is basically completely flat.  Between 2008 and 2013 it's more or less straight up.

What the heck?  Any advice to break through a massive plateau? 

Your comments welcome...