Year	% (national estimate)
1961	50.66
1974	40.38
1981	37.9
1984	42.37
1985	42.97
1986	43.28
1989	67.99
1991	69.22
1996	62.63
2000	61.95
2003	51.61
2006	46.62
2010	46.467
2013	45.417
2016	38.04
2017	40.465
2022	35.822