67% (1984)

71% (1984)

63% (1985)

65% (1987)

73% (1986)

69% (1986)

62% (1980)

68% (1983)

57% (1975)

63% (1980)

53% (1973)

53% (1974)

69% (1968)

71% (1988)

68% (1976)

61% (1971)

57% (1988)

54% (1973)

66% (1976)

0% (1968)