55% (1987)

57% (1975)

68% (1971)

51% (1978)

42% (1976)

65% (1971)

48% (1977)

45% (1978)

66% (1977)

60% (1978)

62% (1970)

52% (1979)

55% (1988)

58% (1969)

75% (1971)

54% (1988)

56% (1971)

50% (1971)

58% (1970)

63% (1964)