64% (1975)

73% (1978)

40% (1987)

65% (1976)

68% (1981)

70% (1978)

54% (1985)

63% (1984)

75% (1984)

70% (1977)

55% (1977)

64% (1987)

45% (1973)

63% (1987)

73% (1985)

78% (1981)

67% (1984)

65% (1984)

70% (1978)

70% (1984)