82% (1992)

71% (1994)

69% (1996)

63% (1993)

65% (1994)

62% (1993)

60% (1997)

49% (1994)

63% (1992)

64% (1997)

51% (1998)

67% (1992)

51% (1996)

40% (1998)

39% (1994)

61% (1996)

43% (1994)

50% (1993)

40% (1997)

46% (1994)