58% (1977)

51% (1985)

65% (1966)

67% (1979)

64% (1971)

62% (1979)

60% (1966)

60% (1981)

35% (1973)

70% (1981)

58% (1974)

56% (1980)

55% (1981)

58% (1971)

64% (1983)

65% (1979)

58% (1980)

62% (1972)

72% (1978)

67% (1975)