Year Percent 2000 82.71111 2001 82.6648 2002 82.61695 2003 82.56755 2004 82.51662 2005 82.46414 2006 82.41012 2007 82.35456 2008 82.29746 2009 82.23881 2010 82.17863 2011 82.1169 2012 82.05363 2013 81.98882 2014 81.92247 2015 81.85457 2016 81.78514 2017 81.71416 2018 81.64164 2019 81.56758 2020 81.49198 2021 81.41484 2022 81.6294