82% (1992)

70% (1996)

61% (1997)

64% (1992)

60% (1996)

63% (1993)

63% (1993)

65% (1994)

66% (1992)

66% (1997)

69% (1996)

51% (1998)

64% (1997)

51% (1996)

48% (1995)

40% (1997)

43% (1994)

59% (1996)

39% (1994)

51% (1989)