65% (1968)

62% (1971)

63% (1971)

55% (1968)

45% (1972)

47% (1972)

53% (1968)

58% (1973)

59% (1972)

51% (1971)

62% (1967)

59% (1971)

49% (1970)

48% (1969)

49% (1969)

47% (1970)

40% (1969)

58% (1969)

52% (1972)

45% (1968)