Year	% (national estimate)
1980	78.63
1981	78.13
1982	77.59
1983	76.04
1984	76.04
1985	76.44
1986	77.19
1987	77.29
1988	76.12
1989	73.24
1990	72.183
1991	70.275
1992	69.579
1993	69.001
1994	69.899
1995	69.628
1996	72.388
1997	74.288
1998	75.808
1999	75.236
2000	75.506
2001	75.16
2002	74.63
2003	73.054
2004	72.533
2005	72.372
2006	72.802
2007	73.901
2008	74.773
2009	72.886
2010	71.923
2011	71.413
2012	71.648
2013	71.118
2014	70.771
2015	70.354
2016	69.338
2017	68.987
2018	69.933
2019	66.849
2020	62.445
2021	68.225
2022	66.923
2023	66.649