75% (1997)

73% (1995)

66% (1997)

74% (1999)

74% (1998)

71% (1996)

54% (1996)

57% (1997)

54% (1995)

64% (1992)

65% (1993)

62% (1993)

62% (1997)

55% (1999)

76% (1994)

51% (1992)

68% (1998)

50% (1996)

52% (1997)

67% (1998)