Year Percent 2011-01-01 2.2911200000000003 2012-01-01 2.2911200000000003 2013-01-01 2.2911200000000003 2014-01-01 2.0040800000000000 2015-01-01 2.0040800000000000 2016-01-01 2.0040800000000000 2017-01-01 3.5745400000000003