51% (1967)

43% (1977)

45% (1969)

56% (2001)

52% (1973)

44% (1986)

46% (1986)

52% (2001)

68% (1973)

50% (1972)

72% (2006)

65% (1977)

80% (2020)

61% (1969)

60% (1995)

53% (2002)

52% (2006)

20% (1985)

35% (1985)

0% (1961)