80% (1996)

81% (1984)

68% (1994)

72% (1998)

73% (1993)

69% (1992)

76% (1996)

70% (1997)

69% (1998)

71% (1994)

68% (1985)

66% (1999)

59% (1991)

71% (1995)

73% (1996)

69% (1986)

63% (1994)

75% (1988)

64% (1997)

71% (1990)