Year	% (national estimate)
1971	17.13
1974	17.72
1978	19.89
1979	30.59
1981	32.47
1983	32.4
1985	33.16
1986	31.58
1987	29.63
1988	32.26
1989	31.08
1990	28.68
1992	33.6
1994	34.4
1997	36.9
2000	39.85
2007	47.63
2008	49.63
2009	47.89
2010	47.343
2011	46.313
2012	48.467
2013	48.786
2014	49.718
2015	47.911
2016	48.035
2019	45.962
2020	44.373
2021	43.878
2022	44.919