Year	% (national estimate)
1970	47.85
1975	50.7
1976	53.72
1977	55.33
1978	56.59
1979	59.26
1980	63.51
1982	61.91
1983	60.92
1984	59.85
1985	57.93
1986	56.39
1987	55.69
1988	55.99
1989	56.39
1992	42.63
1993	40.91
1994	40.65
1995	35.41
1996	36.25
1997	34.19
1998	28.75
2000	26.91
2006	38.68
2007	35.22
2008	36.74
2009	33.66
2010	37.55
2011	35.64
2012	36.38
2013	34.49
2014	35.44
2015	39.79
2016	37.69
2017	35.73
2018	36.93
2019	37.91
2020	35.43
2021	42.316
2022	35.073