72% (1981)

65% (1984)

47% (1984)

39% (1977)

79% (1976)

67% (1977)

51% (1976)

65% (1979)

66% (1976)

49% (1995)

50% (1979)

54% (1987)

56% (1979)

59% (1978)

47% (1976)

52% (1978)

42% (1977)

51% (1983)

48% (1977)

50% (1981)