Year Percent 1991 53.904 1992 51.324 1993 50.996 1994 51.684 1995 51.794 1996 48.918 1997 49.996 1998 52.471 1999 48.074 2000 53.242 2001 51.095 2002 52.488 2003 48.032 2004 50.97 2005 52.411 2006 54.768 2007 54.904 2008 53.364 2009 53.614 2010 52.104 2011 50.318 2012 50.836 2013 48.927 2014 49.244 2015 50.945 2016 51.298 2017 51.714 2018 51.088 2019 50.451 2020 49.787 2021 49.111 2022 48.409