53% (1982)

42% (1997)

61% (1975)

55% (1973)

56% (1977)

40% (1980)

56% (1977)

63% (1974)

45% (1970)

67% (1970)

20% (1989)

60% (1969)

52% (1970)

69% (1976)

62% (1976)

30% (1990)

10% (1973)

50% (1972)

42% (1973)

45% (1963)