Year Percent 2000 64.60221 2001 64.594 2002 64.58579 2003 64.57758 2004 64.56937 2005 64.56116 2006 64.55295 2007 64.54474 2008 64.53653 2009 63.38462 2010 62.233 2011 61.08167 2012 59.93063 2013 58.77988 2014 57.62943 2015 56.47926 2016 55.32939 2017 54.1798 2018 54.1729 2019 54.166 2020 54.1591 2021 54.1522 2022 54.1453