62% (1978)

60% (1970)

67% (1983)

59% (1980)

59% (1979)

55% (1980)

65% (1970)

66% (1975)

49% (1983)

60% (1980)

52% (1980)

67% (1980)

80% (1989)

72% (1971)

67% (1985)

66% (1971)

59% (1977)

63% (1971)

71% (1974)

62% (1976)