68% (1985)

73% (1987)

67% (1980)

59% (1986)

69% (1988)

68% (1987)

69% (1985)

77% (1986)

66% (1986)

69% (1984)

55% (1991)

61% (1986)

70% (1987)

61% (1984)

58% (1982)

70% (1987)

30% (1986)

43% (1989)

66% (1988)

68% (1990)