20% (1989)

30% (1991)

20% (2000)

54% (2008)

20% (1980)

54% (2012)

54% (2004)

20% (1979)

43% (1984)

62% (1985)

71% (2007)

53% (2007)

35% (2009)

30% (2010)

57% (2005)

0% (1984)

20% (2011)

0% (1978)

10% (1985)

60% (2007)