Year Percent 2000 98.35624 2001 98.34854 2002 98.3409 2003 98.33334 2004 98.32881 2005 98.31888 2006 98.311 2007 98.30514 2008 98.30126 2009 98.29934 2010 98.29926 2011 98.30131 2012 98.30555 2013 98.31192 2014 98.32036 2015 98.33086 2016 98.34333 2017 98.35775 2018 98.374 2019 98.39199 2020 98.65157 2021 99.18792 2022 99.17887