67% (1981)

51% (1990)

63% (1980)

71% (1979)

77% (1979)

78% (1980)

72% (1982)

63% (1981)

76% (1980)

50% (1984)

64% (1975)

65% (1981)

41% (1984)

62% (1990)

68% (1991)

53% (1979)

53% (1981)

68% (1981)

70% (1988)

63% (1981)