70% (1992)

78% (2004)

74% (2002)

71% (1988)

53% (2008)

70% (2002)

77% (1999)

67% (1989)

62% (1997)

67% (2008)

72% (2004)

71% (1979)

54% (2005)

68% (1993)

77% (1986)

61% (1995)

69% (1971)

72% (1994)

60% (1999)

59% (1976)