I just counted my 2016 total, and I came in at just over $80, which is well under my goal of $20 per month. No kudos deserved, because I 'over' over stockpiled for 3-4 years in anticipation of my retirement this year. So I literally have thousands of books to read.
Nevertheless I'm pleased with 2016. I was able to break the really bad habit of visiting Amazon daily deals several times a week. I hate to think about what I probably spent there on books I may never read
In 2017 my goal is to make intentional purchases of books I intend to read right away, like the next Liaden to come out. No more books on spec. And to keep picking away at the stockpile.