67% (1981)

47% (1984)

43% (1983)

71% (1979)

70% (1984)

63% (1985)

61% (1983)

65% (1981)

64% (1980)

45% (1984)

58% (1988)

59% (1984)

20% (1991)

73% (1994)

60% (1987)

62% (1980)

62% (1982)

52% (1985)

63% (1977)

61% (1985)