Year Percent 2010-01-01 1.7226599999999999 2011-01-01 1.4471100000000001 2012-01-01 1.1376700000000002 2013-01-01 0.9040610000000000 2014-01-01 0.7674470000000000 2015-01-01 0.6844500000000000 2016-01-01 0.6343620000000000