Year % (national estimate) 1981 50.849764934465846 1983 50.63479960894872 1984 52.99006415482632 1985 52.31176552068959 1986 52.17511665330206 1987 52.74329735545971 1988 52.23138650632196 1989 51.26855469074967 1990 51.019393043406296 1991 49.593927791288614 1992 47.584814847844214 1993 45.98270153156127 1994 44.808471138676396 1995 43.71594286067545 1996 42.802035146205505 1997 42.525211393337784 1998 43.16874778895646 1999 43.96321993518707 2000 44.07663741878455 2001 43.62627435960875 2002 43.738225032421866 2003 43.48049061643327 2004 43.20010027440925 2005 42.87785244663591 2006 42.95270061151626 2007 43.21280290483984 2008 43.36091273626368 2009 42.522064655282925 2010 41.50291402575669 2011 40.83965609514126 2012 40.46362280138126 2013 40.52661037491969 2014 39.77292111901123 2015 39.305046795128625 2016 39.243167670612344 2017 39.37552907713941 2018 39.54917333292661 2019 39.64875208793377 2020 38.03632479867292 2021 40.48586433511045 2022 41.81811443251334 2023 42.80480587605615