53% (1979)

49% (1977)

54% (1981)

74% (1974)

63% (1968)

53% (1980)

55% (1987)

64% (1980)

48% (1989)

54% (2009)

65% (2002)

53% (1980)

54% (1982)

56% (1980)

52% (1978)

52% (1979)

71% (1973)

52% (1988)

66% (1974)

74% (1975)