73% (1995)

74% (1997)

74% (1999)

54% (1995)

66% (1997)

73% (1998)

65% (1993)

63% (1992)

63% (1997)

57% (1997)

55% (1999)

67% (1998)

54% (1996)

48% (1992)

61% (1993)

56% (1997)

43% (1996)

67% (1998)

52% (1997)

50% (1996)