Year	% (national estimate)
1960	40.2
1971	42.24
1982	43.028
1990	35.7
1994	46.123
1995	42.62
1998	36.74
1999	48.01
2000	46.5
2001	42.52
2002	41.66
2003	43.09
2004	43.99
2005	42.56
2006	39.82
2007	43.71
2008	38.94
2009	39.83
2010	36.27
2011	34.99
2012	33.5
2013	32.23
2014	32.31
2015	30.37
2016	28.7