76% (1977)

70% (1987)

62% (1988)

70% (1965)

69% (1985)

69% (1969)

62% (1968)

62% (1974)

70% (1976)

65% (1930)

53% (1929)

63% (1967)

49% (1966)

50% (1963)

45% (1959)

61% (1955)

51% (1957)

51% (1985)

64% (1931)

42% (1968)