71% (1981)

76% (1967)

67% (1980)

74% (1968)

66% (1981)

56% (1972)

69% (1970)

56% (1980)

57% (1980)

67% (1971)

62% (1974)

62% (1974)

58% (1973)

61% (1979)

45% (1970)

62% (1982)

58% (1981)

59% (1977)

60% (1981)

48% (1971)