2017 5.61808219178082
2016 5.4379781420765
2015 4.10986301369863
2014 3.89890410958904
2013 5.73890410958904
2012 4.94699453551913
2011 7.3786301369863
2010 6.83945205479452
2009 4.50465753424658
2008 5.51912568306011
2007 4.81643835616438
2006 5.49041095890411
2005 5.4372602739726
2004 6.48087431693989
2003 4.15945205479452
2002 4.37178082191781
2001 4.85205479452055