45% (1981)

51% (1977)

49% (1978)

62% (1964)

51% (1988)

46% (1989)

55% (1980)

52% (1972)

56% (1969)

49% (1987)

54% (1968)

53% (1967)

54% (1980)

45% (1976)

49% (1990)

45% (1988)

35% (1988)

47% (1987)

61% (1972)

57% (1964)