45% (1983)

44% (1987)

39% (1984)

57% (1985)

57% (1970)

20% (1987)

56% (1986)

55% (1967)

60% (1984)

48% (1974)

61% (1968)

54% (1973)

37% (1988)

69% (1969)

51% (1971)

45% (1985)

49% (1969)

62% (1975)

63% (1971)

56% (1969)