50% (1981)

46% (1980)

52% (1981)

50% (1978)

57% (1972)

67% (1982)

47% (1974)

52% (1980)

49% (1981)

54% (1973)

37% (1978)

0% (1983)

37% (1974)

52% (1980)

46% (1970)

55% (1973)

56% (1977)

42% (1969)

40% (1974)

52% (1977)