Year	Percent
1965	66.5
1970	67.6
1973	69.6
1975	79
1976	67.7
1982	69.5
1988	74.3
1990	70.7
1995	76.4
2002	72.8
2007	77.1
2008	77.1
2010	76.4
2012	74.1
2014	72.7
