Year Percent 1991 43.678 1992 44.034 1993 44.078 1994 44.538 1995 44.446 1996 44.578 1997 44.484 1998 44.518 1999 44.879 2000 44.909 2001 44.356 2002 44.602 2003 45.077 2004 45.844 2005 46.217 2006 46.902 2007 47.669 2008 47.801 2009 47.161 2010 47.646 2011 48.018 2012 48.334 2013 48.638 2014 48.861 2015 49.045 2016 48.847 2017 48.66 2018 48.426 2019 48.077 2020 47.853 2021 47.641 2022 47.424