72% (1991)

57% (1994)

65% (1997)

76% (1992)

60% (1994)

63% (1996)

62% (1992)

65% (1993)

64% (1998)

60% (1996)

63% (1998)

56% (1992)

59% (1991)

55% (1997)

57% (1998)

56% (1999)

48% (1996)

70% (1991)

48% (1997)

68% (1996)