Year	% (national estimate)
1978	75.14
1979	75.95
1980	75.05
1981	75.46
1982	74.21
1984	74.33
1985	68.57
1986	68.468
1987	68.203
1988	68.837
1989	69.766
1990	69.349
1991	70.723
1992	68.445
1993	66.214
1994	64.481
1995	63.45
1996	62.85
1997	63.232
1998	67.547
1999	66.965
2000	67.597
2001	68.188
2002	68.063
2003	66.338
2004	65.624
2005	64.516
2006	64.75
2007	64.569
2008	64.456
2009	61.731
2010	60.653
2011	58.794
2012	55.97
2013	54.666
2014	55.793
2015	56.295
2016	57.052
2017	59.09
2018	60.169
2019	60.642
2020	58.839
2021	58.468
2022	59.623
2023	59.971