Year Percent 1991 44.84 1992 44.763 1993 44.552 1994 44.163 1995 43.94 1996 44.067 1997 43.806 1998 43.731 1999 43.55 2000 43.39 2001 43.517 2002 43.576 2003 43.649 2004 43.48 2005 43.4 2006 43.607 2007 43.783 2008 43.92 2009 43.943 2010 43.846 2011 44.301 2012 44.673 2013 45.161 2014 45.213 2015 45.307 2016 45.195 2017 45.534 2018 45.868 2019 46.191 2020 46.5 2021 46.812 2022 47.114