60% (1956)

38% (1978)

43% (1990)

46% (1986)

52% (1970)

60% (1976)

10% (1966)

68% (1961)

38% (1985)

10% (1973)

40% (1989)

55% (1980)

54% (1977)

64% (1981)

80% (1955)

60% (1964)

55% (1982)

48% (1978)

0% (1983)

58% (1959)