Speaking only for myself, no social life to speak of. 
I set my goal at 52 books this year — a book a week. I know that I can, and likely will, read more than that (I read 68 in 2013, an all-time high for me), but I don’t like to set my goal too high because then I start doing things like only choosing shorter and/or easier books. There are a few really thick books that have been sitting on my shelf that I’d like to get through this year. Right now I’m doing a challenge through my library, so I’m starting the year by trying to check out more library books.