Year Percent 2000 97.80272 2001 97.79932 2002 97.84864 2003 97.89956 2004 97.95436 2005 98.00888 2006 98.06018 2007 98.11085 2008 98.16173 2009 98.21362 2010 98.26636 2011 98.31903 2012 98.37163 2013 98.42415 2014 98.47659 2015 98.52896 2016 98.58136 2017 98.63375 2018 98.68607 2019 98.73825 2020 98.79026 2021 98.84204 2022 98.89353