58% (1980)

71% (1981)

66% (1994)

62% (2007)

62% (1997)

62% (1979)

63% (1970)

58% (1991)

52% (2005)

46% (1980)

61% (1987)

62% (2002)

68% (1973)

43% (1970)

44% (1976)

20% (1991)

50% (1976)

54% (1985)

53% (1986)

57% (1974)