Where did the following year's offense rank, and what kept it from being elite?

Only looking at three point attempts, the 2015-2016 offense took 100 more 3s at basically the same conversion %. Educate me on what metrics held that year down.

2016-2017: 668 attempts, 34%
2015-2016: 863 attempts, 38%
2014-2015: 763 attempts, 39%
2013-2014: 498 attempts, 36%
2012-2013: 630 attempts, 34%
2011-2012: 679 attempts, 34%
2010-2011: 865 attempts, 36%
2009-2010: 700 attempts, 42%