Year	% (national estimate)
1961	85.46
1971	81.04
1978	71.32
1979	72.78
1980	71.02
1990	63.67
1991	58.37
1992	70.19
1993	70.92
1994	69.98
1995	69.76
1996	66.42
1997	64.57
1998	67.05
1999	65.66
2002	60.77
2003	64.43
2004	62.65
2006	63.38
2007	64.05
2009	67.26
2010	63.114
2011	63.109
2012	63.092
2013	61.747
2014	61.302
2015	60.507
2016	61.026
2017	61.793
2018	60.326
2019	62.674
2020	58.94
2021	61.765
2022	61.557