Year	% (national estimate)
1976	70.51
1978	76.36
1979	73.75
1980	85.26
1982	73.36
1984	75.98
1987	79.52
1988	82.52
1989	83.47
1990	82.01
1994	77.66
1996	73.95
1997	74.38
2000	73.429
2007	74.044
2009	71.39
2010	71.148
2011	72.71
2012	72.51
2013	70.097
2014	69.43
2015	68.822
2016	67.78
2017	66.941
2018	67.28
2019	66.484
2020	66.284
2021	66.125
2022	66.903
2023	67.739