49% (1971)

42% (1973)

47% (1974)

30% (1983)

54% (1985)

37% (1973)

55% (1977)

50% (1975)

54% (1970)

43% (1971)

45% (1985)

51% (1971)

55% (1985)

20% (1987)

62% (1986)

60% (1973)

10% (1986)

20% (1973)

0% (1987)