61% (1986)

63% (1985)

71% (1992)

73% (1994)

70% (1993)

64% (1997)

73% (1998)

60% (1998)

64% (1988)

72% (1992)

66% (1997)

56% (1989)

61% (1996)

61% (1995)

63% (1988)

62% (1994)

65% (1989)

71% (1990)

60% (1987)

10% (1994)