70% (1983)

69% (2006)

64% (2012)

35% (2010)

29% (2011)

61% (1989)

36% (2008)

20% (1988)

50% (2000)

35% (2009)

40% (2007)

20% (2008)

35% (2005)

60% (2009)

80% (2007)

40% (2009)

40% (1998)