79% (1962)

78% (1977)

71% (1979)

57% (1984)

57% (1988)

57% (1987)

45% (1973)

59% (1980)

67% (1989)

50% (1990)

0% (1983)

47% (1980)

73% (1966)

56% (1965)

0% (1985)