59% (1976)

67% (1974)

61% (1997)

62% (1974)

54% (1983)

77% (1986)

68% (1993)

70% (1995)

77% (1969)

70% (1976)

51% (1972)

66% (2007)

76% (1967)

57% (2007)

64% (1991)

63% (1983)

71% (1969)

57% (2001)

56% (2002)

61% (1974)