52% (1981)

45% (1980)

48% (1974)

56% (1973)

51% (1978)

67% (1982)

52% (1980)

55% (1977)

50% (1981)

50% (1981)

66% (1973)

37% (1978)

44% (1970)

34% (1974)

30% (1976)

57% (1980)

30% (1978)

42% (1974)

45% (1977)

42% (1969)