72% (1954)

74% (1970)

58% (1950)

50% (1977)

61% (1969)

54% (1973)

38% (1965)

49% (1966)

70% (1965)

61% (1979)

67% (1988)

52% (1970)

46% (1991)

56% (1965)

66% (1967)

64% (1958)

46% (1990)

56% (1968)

60% (1982)

53% (1939)