Year Percent 2009-01-01 2.3211300000000000 2010-01-01 2.3825200000000000 2011-01-01 2.7446900000000003 2012-01-01 3.1540700000000000 2013-01-01 3.3802800000000004 2014-01-01 3.2934300000000003 2015-01-01 4.8864900000000000 2016-01-01 6.7133000000000000