Year Percent 2011-01-01 6.1927900000000005 2012-01-01 6.1927900000000005 2013-01-01 6.1927900000000005 2014-01-01 2.3595800000000000 2015-01-01 2.3595800000000000 2016-01-01 2.3595800000000000 2017-01-01 2.7935200000000000