65% (1987)

57% (1992)

41% (1994)

58% (1988)

59% (1987)

57% (1993)

67% (1991)

68% (1990)

63% (1996)

55% (1996)

69% (1991)

60% (1994)

58% (1988)

52% (1988)

56% (1987)

63% (1995)

64% (1993)

49% (1994)

61% (1991)

55% (1992)