71% (1998)

70% (1995)

64% (1993)

61% (1998)

69% (1997)

65% (1997)

62% (1995)

67% (1995)

60% (1994)

45% (1999)

55% (1994)

70% (1995)

68% (1998)

57% (1996)

60% (1996)

52% (1997)

57% (1994)

57% (1997)

48% (1997)

55% (1995)