Year	% (national estimate)
1977	52.89
1979	68.53
1980	54.9
1981	69.39
1982	71.46
1984	68.51
1985	68.57
1986	67.97
1987	67.7
1988	67.71
1989	69.75
1990	72.243
1991	67.422
1992	61.971
1993	58.063
1994	57.347
1995	54.562
1996	54.45
1997	56.137
1998	57.364
1999	60.704
2000	61.423
2001	61.672
2002	60.815
2003	60.29
2004	59.948
2005	60.235
2006	60.774
2007	61.021
2008	61.854
2009	58.547
2010	58.247
2011	58.894
2012	58.416
2013	57.404
2014	56.696
2015	56.318
2016	56.749
2017	57.116
2018	58.457
2019	58.544
2020	57.845
2021	59.038
2022	59.655
2023	58.778