59% (1980)

50% (1983)

47% (1960)

40% (1980)

52% (1982)

27% (1964)

49% (1985)

38% (1977)

52% (1976)

53% (1985)

53% (1980)

46% (1977)

46% (1980)

54% (1978)

65% (1980)

43% (1974)

44% (1961)

56% (1987)

47% (1989)

41% (1976)