Year % (national estimate) 1960 59.85 1976 42.99 1988 57.94 1989 62.41 1990 61.76 1991 62.42 1992 51.7 1995 55.06 1999 41.156 2000 40.412 2001 42.519 2002 39.807 2003 41.232 2004 41.804 2005 42.936 2006 41.721 2007 41.718 2008 41.776 2009 40.461 2010 40.615 2011 38.856 2012 39.184 2013 38.524 2014 40.367 2015 37.976 2016 37.221 2017 36.807 2018 39.431 2019 38.951 2020 38.432 2021 41.96 2022 42.325 2023 43.871