77% (1994)

73% (1991)

68% (1986)

54% (1979)

73% (1984)

67% (1988)

56% (1985)

59% (1986)

82% (1993)

62% (1983)

73% (1979)

60% (1988)

78% (1988)

54% (1983)

57% (1980)

72% (1992)

58% (1988)

60% (1985)

50% (1994)

58% (1985)