44% (1972)

50% (1981)

56% (1973)

58% (1979)

58% (1971)

43% (1973)

51% (1977)

54% (1973)

55% (1970)

46% (1975)

71% (1977)

50% (1981)

55% (1969)

60% (1974)

49% (1971)

48% (1972)

49% (1973)

47% (1980)

53% (1968)

44% (1974)