57% (1968)

68% (1970)

42% (1976)

60% (1965)

40% (1972)

60% (1971)

63% (1967)

76% (1966)

55% (1965)

47% (1972)

45% (1978)

41% (1964)

62% (1960)

60% (1968)

65% (1985)

64% (1989)

48% (1971)

61% (1963)

56% (1978)

63% (1970)