64% (1975)

65% (1976)

45% (1973)

80% (1981)

81% (1981)

63% (1988)

73% (1985)

70% (1982)

60% (1984)

73% (1984)

75% (1980)

55% (1977)

63% (1974)

70% (1978)

70% (1987)

70% (1978)

62% (1983)

70% (1984)

68% (1981)

80% (1979)