63% (1997)

61% (1977)

57% (1972)

57% (1983)

57% (2007)

76% (1967)

56% (2002)

64% (1996)

52% (1972)

53% (1999)

54% (1983)

47% (1984)

67% (1975)

64% (1999)

55% (1997)

54% (1998)

63% (1983)

67% (1976)

62% (1978)

66% (1977)