Year Percent 2005-01-01 77.0777605801985 2006-01-01 79.1361499038382 2007-01-01 80.2270114544978 2008-01-01 81.2507645709069 2009-01-01 81.4637368632998 2010-01-01 82.1894311236559 2011-01-01 82.9279446585639 2012-01-01 85.0072551064942 2013-01-01 85.6679115014319 2014-01-01 85.7628418379598 2015-01-01 85.6449677615189 2016-01-01 84.8293800827261 2017-01-01 86.2111328749986