66% (1981)

48% (1984)

44% (1983)

55% (1983)

71% (1979)

62% (1983)

63% (1985)

53% (1985)

66% (1981)

64% (1982)

60% (1984)

60% (1985)

63% (1980)

76% (1980)

63% (1977)

62% (1980)

70% (1984)

60% (1987)

54% (1985)

56% (1979)