74% (2002)

71% (1992)

78% (2004)

76% (1986)

76% (1999)

53% (2008)

54% (2005)

72% (1994)

60% (1999)

67% (2008)

60% (1972)

71% (1988)

68% (1993)

71% (1979)

62% (1997)

71% (2004)

70% (2002)

63% (1980)

62% (1974)

63% (1983)