76% (2010)

65% (2013)

64% (2017)

56% (2011)

57% (2015)

56% (2011)

54% (2011)

61% (2007)

65% (2006)

59% (2008)

66% (2010)

55% (2012)

62% (2009)

64% (2010)

57% (2008)

54% (1999)

41% (2003)

55% (2009)

39% (1994)

47% (1997)