68% (1984)

56% (1975)

50% (1976)

65% (1985)

0% (1971)

0% (1977)

65% (1987)

68% (1983)

71% (1988)

69% (1986)

60% (1968)

54% (1973)

73% (1986)

54% (1973)

0% (1963)

0% (1961)

40% (1984)

72% (1984)

68% (1976)

64% (1980)