71% (1998)

65% (1997)

70% (1995)

70% (1995)

64% (1993)

61% (1998)

62% (1995)

45% (1999)

60% (1994)

67% (1995)

53% (1998)

48% (1997)

55% (1995)

69% (1998)

57% (1997)

52% (1997)

57% (1994)

59% (1996)

63% (1995)

69% (1997)