62% (1963)

64% (1965)

65% (1974)

53% (1967)

66% (1973)

63% (1965)

51% (1980)

62% (1980)

58% (1980)

49% (1981)

44% (1981)

59% (1971)

70% (1967)

69% (1981)

45% (1966)

55% (1968)

50% (1979)

57% (1969)

60% (1980)

59% (1978)