Hello,
My background check took around 14 months, my AOR was October 11, 2015 & I got PPR on April 20, 2017.
You're not the only one,

there are many more applicants going through the prolonged background checks [comprehensive screening]. You can find similar timelines in the thread for applicants who are waiting for more than 6 months, there's one for those who have crossed 15 months, as well.
Just hang in there and keep yourself busy.
Hopefully IRCC will come up with something better, soon, to cut down these security check/screening delays.
Good luck!