80% (1996)

68% (1994)

72% (1998)

69% (1998)

70% (1997)

73% (1993)

66% (1999)

67% (1985)

70% (1995)

76% (1996)

73% (1996)

70% (1990)

62% (1998)

73% (1992)

60% (1996)

62% (1994)

71% (1990)

63% (1988)

90% (1984)

0% (1991)