Year Percent 1991 1.775 1992 1.824 1993 1.833 1994 1.809 1995 1.79 1996 1.77 1997 1.733 1998 1.7 1999 1.714 2000 1.752 2001 1.679 2002 1.647 2003 1.911 2004 1.862 2005 1.872 2006 1.834 2007 1.864 2008 1.883 2009 1.868 2010 1.896 2011 1.951 2012 1.892 2013 1.865 2014 1.868 2015 1.888 2016 1.869 2017 1.898 2018 1.9 2019 1.903 2020 1.904 2021 1.892 2022 1.882