Year	% (national estimate)
1976	51.402
1977	51.564
1978	52.372
1979	54.647
1980	56.113
1981	57.241
1982	53.926
1983	53.923
1984	54.998
1985	56.613
1986	58.258
1987	59.443
1988	60.887
1989	61.905
1990	59.916
1991	57.573
1992	55.125
1993	53.268
1994	53.4
1995	53.257
1996	52.047
1997	50.159
1998	51.94
1999	53.756
2000	55.715
2001	56.219
2002	57.62
2003	58.636
2004	58.254
2005	58.74
2006	60.284
2007	60.971
2008	61.27
2009	58.349
2010	57.889
2011	57.719
2012	57.438
2013	57.915
2014	58.257
2015	58.537
2016	58.219
2017	58.874
2018	58.467
2019	59.924
2020	49.894
2021	56.185
2022	60.158
2023	58.606