76% (1980)

68% (1977)

65% (2000)

64% (2006)

67% (1976)

55% (1994)

67% (1978)

56% (1996)

59% (1984)

49% (1978)

65% (1978)

62% (1994)

66% (1994)

55% (1985)

56% (1983)

80% (1996)

59% (2011)

51% (1976)

55% (1995)

68% (1981)