Year Percent 2000 28.05522 2001 28.34986 2002 28.78981 2003 29.24864 2004 29.69821 2005 30.13608 2006 30.56328 2007 30.97873 2008 31.3826 2009 31.77232 2010 32.15005 2011 32.51371 2012 32.87362 2013 33.21906 2014 33.54989 2015 33.86497 2016 34.15867 2017 34.43011 2018 34.67975 2019 34.96077 2020 35.25997 2021 35.55342 2022 35.84054