45% (2000)

43% (1981)

83% (1973)

45% (1986)

50% (2007)

56% (1990)

31% (1995)

70% (1978)

35% (1984)

54% (1977)

60% (1971)

64% (1969)

60% (1973)

47% (2002)

60% (1979)

40% (2006)

20% (1985)

50% (2005)

65% (1969)

0% (1977)