68% (1978)

68% (2009)

74% (1993)

65% (1986)

74% (1998)

62% (1991)

69% (1984)

49% (1999)

61% (1990)

70% (1992)

65% (1999)

69% (2011)

61% (1993)

44% (1994)

0% (1975)

59% (2008)

64% (1978)

78% (1994)

42% (1994)

71% (1987)