Year Percent 2011-01-01 3.1671400000000003 2012-01-01 3.1671400000000003 2013-01-01 3.1671400000000003 2014-01-01 8.7177600000000000 2015-01-01 8.7177600000000000 2016-01-01 8.7177600000000000 2017-01-01 11.9812000000000000