69% (1998)

78% (1994)

78% (1989)

68% (2007)

67% (2008)

76% (2000)

67% (1987)

78% (1984)

69% (2005)

66% (2009)

62% (2012)

66% (1994)

59% (1998)

63% (2009)

50% (2009)

53% (2008)

62% (1995)

68% (2008)

63% (2009)

50% (1993)