60% (1976)

64% (1972)

71% (1972)

71% (1978)

64% (1980)

60% (1977)

63% (1975)

62% (1976)

52% (1979)

56% (1977)

63% (1979)

69% (1975)

42% (1978)

59% (1972)

54% (1972)

65% (1978)

61% (1974)

64% (1973)

58% (1978)

48% (2017)