68% (1994)

76% (1996)

79% (1996)

78% (1998)

76% (1997)

61% (1997)

72% (1998)

70% (1990)

73% (1994)

66% (1992)

60% (1997)

60% (1996)

59% (1991)

72% (1998)

74% (1999)

82% (1998)

70% (1999)

71% (1994)

59% (1998)

65% (1998)