Year	% (national estimate)
1978	54.55
1979	54.21
1981	53.16
1985	51.52
1986	51.37
1987	51.33
1988	51.88
1989	51.81
1990	51.53
1991	48.5
1992	58.966
1993	54.899
1994	54.347
1995	54.702
1996	51.566
1997	51.582
1998	51.755
1999	53.817
2000	54.285
2001	54.076
2002	54.055
2003	54.615
2004	54.444
2005	54.233
2006	54.762
2007	54.55
2008	53.668
2009	51.934
2010	51.126
2011	51.873
2012	52.529
2013	54.026
2014	57.176
2015	58.939
2016	61.041
2017	62.691
2018	63.474
2019	64.21
2020	63.577
2021	64.441
2022	65.234
2023	65.567