57% (1997)

71% (2008)

72% (2013)

58% (2007)

52% (2010)

54% (2014)

46% (2012)

55% (2011)

15% (2006)

50% (2012)

57% (2008)

56% (1980)

35% (2005)

33% (2010)

37% (1962)

90% (1995)

45% (2003)

66% (2002)

64% (1999)

53% (2004)