2017 4.9972602739726
2016 5.58770491803279
2015 3.6958904109589
2014 3.72082191780822
2013 5.11561643835616
2012 4.69918032786885
2011 7.00712328767123
2010 5.69808219178082
2009 4.1372602739726
2008 5.15491803278689
2007 2.98922155688623
2006 4.12739726027397
2005 5.51315068493151
2004 5.9448087431694
2003 3.55205479452055
2002 3.89452054794521
2001 3.61736526946108