58% (1987)

61% (1992)

68% (1989)

58% (1990)

64% (1987)

46% (1994)

55% (1987)

63% (1995)

60% (1994)

57% (1993)

64% (1995)

55% (1996)

64% (1993)

62% (1994)

68% (1994)

66% (1990)

58% (1992)

60% (1958)

51% (1988)

71% (1994)