72% (1981)

65% (1984)

47% (1984)

39% (1977)

67% (1977)

79% (1976)

49% (1995)

65% (1979)

77% (1974)

51% (1976)

66% (1976)

60% (1975)

50% (1979)

59% (1978)

52% (1978)

50% (1981)

38% (1978)

58% (1976)

56% (1979)

42% (1977)