Year Percent 2009-01-01 0.44921000000000005 2010-01-01 0.50121400000000000 2011-01-01 0.59250500000000010 2012-01-01 0.67164099999999990 2013-01-01 0.83592400000000000 2014-01-01 0.81193300000000000 2015-01-01 0.74889500000000000 2016-01-01 0.84996299999999990