Year Percent 2000 82.56711 2001 82.86552 2002 83.16404 2003 83.46265 2004 83.76137 2005 84.06017 2006 84.35908 2007 84.65809 2008 84.95719 2009 85.25639 2010 85.55569 2011 85.85508 2012 86.15457 2013 86.45417 2014 86.75385 2015 87.05364 2016 87.35352 2017 87.65351 2018 87.95359 2019 88.25376 2020 88.55404 2021 88.55404 2022 88.55404