64% (1973)

72% (1976)

70% (1990)

58% (1967)

68% (1988)

62% (2004)

65% (1975)

72% (1975)

62% (1990)

72% (1975)

70% (1978)

70% (1977)

67% (1973)

60% (1980)

70% (1973)

80% (1987)

55% (1976)

45% (1986)

63% (1989)

40% (1969)