The last time I added a new movie my top 250 was Remember the Night, which I saw in March 2014. I have very very few "blow me away" experiences these days, partly because 1) I've seen most of the acknowledged classics and an awful lot of the hidden gems that are likely to appeal to me, and 2) I don't watch nearly as many movies as I used to. On the up side, because I've gotten so much more selective about what I watch, I very rarely have a bad experience. Of the 55 movies (not counting rewatches or stand-up specials) I've seen in the past year, only 15 were below the "lime green" (mid-to-high "good") range. The rest were all at least pretty decent, very worthwhile.
Of the less-than-good 15 movies, 4 were disappointing true crime docs, 1 was for top 100 club, 1 was Manos: Hands of Fate (so it was entertainingly terrible), and 1 was my wife's choice.
I would say Sing Street (which I saw in October 2016) could possibly enter my top 250 list, as could Watership Down (May 2015). Now that I think about it, so could my watches Teproc's top 100 club: Timbuktu and Our Little Sister.