Year	% (national estimate)
1963	21.81
1971	21.01
1977	27.79
1989	32.12
1990	33.26
1991	33.12
1995	25.46
1996	25.8
1998	26.17
1999	34.92
2000	31.9
2001	30.255
2006	31.21
2012	57.803
2014	32.462