Year	% (national estimate)
1961	70.14
1966	69.84
1971	63.98
1976	64.68
1979	70.474
1980	72.175
1981	72.158
1982	71.753
1983	71.29
1984	71.02
1985	71.217
1986	72.006
1987	71.295
1988	71.038
1989	72.094
1990	72.104
1991	69.657
1992	69.386
1993	68.725
1994	70.576
1995	71.64
1996	71.664
1997	70.06
1998	69.87
1999	69.924
2000	70.182
2001	70.671
2002	69.976
2003	70.222
2004	70.14
2005	70.81
2006	70.802
2007	70.76
2008	70.747
2009	69.1
2010	68.425
2011	68.139
2012	67.52
2013	66.823
2014	66.563
2015	67.264
2016	66.786
2017	66.894
2018	67.85
2019	68.115
2020	66.236
2021	68.575
2022	71.546
2023	71.038