76% (1997)

77% (1996)

75% (1999)

66% (1992)

71% (1990)

60% (1997)

74% (2002)

62% (2002)

69% (1998)

40% (1996)

59% (1993)

65% (1998)

66% (1993)

54% (1995)

58% (1998)

61% (2000)

63% (1991)

58% (1995)

40% (2001)

57% (1992)