72% (1987)

77% (1986)

53% (1986)

54% (1983)

74% (1991)

62% (1988)

70% (1984)

69% (1994)

63% (1989)

60% (1988)

66% (1982)

67% (1990)

68% (1990)

65% (1986)

59% (1990)

66% (1992)

62% (1990)

55% (1991)

52% (1986)

48% (1989)