81% (1979)

83% (1985)

78% (1972)

80% (1975)

76% (1925)

72% (1970)

77% (1965)

69% (1967)

80% (1973)

80% (1957)

80% (1966)

79% (1969)

76% (1980)

79% (1975)

79% (1971)

74% (1975)

79% (1967)

78% (1962)

79% (1977)

80% (1977)