Year Percent 1991 52.266 1992 49.003 1993 50.059 1994 49.239 1995 50.324 1996 53.704 1997 53.148 1998 51.9 1999 52.955 2000 51.804 2001 51.052 2002 53.442 2003 53.957 2004 51.9 2005 50.095 2006 52.639 2007 52.419 2008 51.725 2009 54.159 2010 55.648 2011 56.97 2012 56.916 2013 55.762 2014 50.419 2015 51.635 2016 48.362 2017 48.403 2018 48.205 2019 48.052 2020 47.883 2021 47.678 2022 47.473