72% (1988)

69% (1981)

72% (1981)

67% (1980)

59% (1986)

59% (1980)

64% (1974)

59% (1986)

47% (1979)

64% (1980)

65% (1977)

62% (1974)

61% (1973)

68% (1976)

60% (1978)

33% (1975)

65% (1986)

60% (1975)

53% (1981)

54% (1984)