Year	% (national estimate)
1963	83.62
1971	65.93
1977	68.47
1989	68.28
1990	69.46
1991	70.6
1995	72.11
1996	72.81
1998	74.1
1999	86.35
2000	68.2
2001	70.957
2006	63.46
2012	82.261
2014	71.376