Year % (national estimate) 1986 74.491 1987 73.485 1988 69.961 1989 67.712 1990 68.472 1991 67.392 1992 65.529 1993 64.672 1994 66.029 1995 67.109 1996 66.966 1997 66.71 1998 64.969 1999 62.959 2000 62.674 2001 62.969 2002 63.625 2003 62.405 2004 62.192 2005 62.358 2006 64.42 2007 64.506 2008 63.034 2009 61.373 2010 59.86 2011 59.631 2012 59.274 2013 57.89 2014 60.05 2015 61.398 2016 62.371 2017 63.195 2018 63.724 2019 63.534 2020 62.876 2021 64.85 2022 67.5 2023 68.634