56% (1974)

60% (1961)

57% (1970)

55% (1980)

68% (1970)

61% (1974)

60% (1968)

56% (1975)

50% (1975)

67% (1975)

65% (1962)

62% (1978)

66% (1968)

56% (1970)

44% (1974)

52% (1992)

69% (1991)

49% (1970)

63% (1970)

54% (1973)