Year	% (national estimate)
1970	60.37
1975	58.83
1976	59.73
1977	60.04
1978	61.43
1979	63.34
1980	66.45
1982	65.09
1983	64.75
1984	62.38
1985	60.19
1986	58.66
1987	56.86
1988	55.83
1989	56.19
1992	45.24
1993	43.79
1994	42.62
1995	36.85
1996	38.55
1997	35.67
1998	31.43
2000	27.77
2006	38.9
2007	36.87
2008	37.15
2009	35.58
2010	39.16
2011	36.71
2012	37.78
2013	36.18
2014	37.55
2015	40.59
2016	39.37
2017	38.24
2018	38.13
2019	38.26
2020	36.05
2021	41.346
2022	37.697