Year % (national estimate) 1992 53.51412191147886 1995 50.525742694204695 1996 48.69760376351826 1997 44.893646354007444 1998 45.345755000167564 1999 43.83347538442991 2000 42.94517781052863 2001 42.66659630091035 2002 41.05925412740421 2003 39.529006709299594 2004 38.76975893538722 2005 37.47129511553081 2006 36.362949382228464 2007 36.23788511088886 2008 36.31751291673691 2009 36.69772930112566 2010 36.96176403252215 2011 36.19588715953824 2012 36.25777598487288 2013 36.47363980591647 2014 37.0247166857454 2015 37.293033474181804 2016 37.4949787472881 2017 37.71570599074417 2018 37.09603798544506 2019 36.949349704666446 2020 35.144108882619804 2021 34.047854650592434 2022 33.95900399236356 2023 33.68121355682018