Year	% (national estimate)
1964	50.76
1973	47.58
1978	42.22
1979	46.8
1980	49.3
1981	43.18
1985	45.03
1987	54.01
1989	53.49
1994	44.69
1999	52.55
2003	62.942
2004	55.114
2006	59.13
2010	51.03
2011	53.262
2012	57.916
2013	49.842
2014	51.611
2015	52.241
2016	52.516
2017	52.477
2018	52.406
2019	51.414
2021	55.012
2022	51.612