67% (1983)

68% (1972)

62% (1975)

59% (1971)

53% (1977)

60% (1972)

73% (1982)

67% (1973)

47% (1979)

61% (1980)

62% (1973)

61% (1973)

60% (1976)

62% (1983)

55% (1972)

60% (1973)

42% (1978)

50% (1977)

60% (1973)

20% (1979)