58% (1970)

47% (1975)

57% (1972)

49% (1976)

62% (1978)

50% (1993)

80% (1975)

50% (1976)

53% (1975)

52% (1979)

67% (1977)

64% (1976)

61% (1994)

55% (1975)

62% (1976)

64% (1999)

60% (1985)

67% (1975)

69% (1985)

50% (1968)