Year Percent 2000 84.48083 2001 84.75993 2002 85.03281 2003 85.29916 2004 85.55907 2005 85.81226 2006 86.05913 2007 86.29944 2008 86.53357 2009 86.75949 2010 86.97813 2011 87.18924 2012 87.09354 2013 86.98688 2014 86.86984 2015 86.74252 2016 86.60548 2017 86.45882 2018 86.30309 2019 86.1385 2020 85.96547 2021 85.7843 2022 85.82629