2017 5.6986301369863
2016 5.56284153005465
2015 3.6986301369863
2014 4.15753424657534
2013 5.29178082191781
2012 4.5068306010929
2011 6.40301369863014
2010 5.66027397260274
2009 3.62739726027397
2008 5.06666666666667
2007 3.32904109589041
2006 3.38082191780822
2005 5.92246575342466
2004 5.94016393442623
2003 3.33424657534247
2002 3.18657534246575
2001 3.14684931506849