59% (1976)

70% (1985)

70% (1977)

51% (1988)

60% (1977)

54% (1973)

55% (1974)

57% (1990)

66% (1983)

46% (1970)

67% (1970)

55% (1965)

74% (1962)

49% (1966)

61% (1981)

71% (1973)

32% (1960)

71% (1987)

69% (1964)

71% (1954)