Year	% (national estimate)
1976	57.143
1977	56.879
1978	57.486
1979	58.879
1980	59.426
1981	60.087
1982	57.287
1983	56.947
1984	57.668
1985	58.752
1986	59.764
1987	60.61
1988	61.661
1989	62.187
1990	61.685
1991	59.709
1992	58.345
1993	57.904
1994	58.382
1995	58.673
1996	58.451
1997	58.968
1998	59.735
1999	60.56
2000	61.272
2001	61.149
2002	61.737
2003	62.444
2004	62.638
2005	62.604
2006	62.836
2007	63.307
2008	63.349
2009	61.584
2010	61.569
2011	61.797
2012	61.903
2013	62.047
2014	61.654
2015	61.582
2016	61.283
2017	61.802
2018	61.955
2019	62.295
2020	58.107
2021	60.468
2022	61.982
2023	62.06