67% (1986)

62% (1992)

60% (1988)

60% (2008)

49% (1993)

63% (1990)

72% (1996)

66% (1999)

58% (1997)

68% (1983)

64% (1991)

63% (1981)

68% (1988)

75% (1995)

75% (1983)

52% (1985)

45% (1989)

53% (1986)

84% (1980)

45% (1993)