2017 10.0167123287671
2016 9.73633879781421
2015 7.93671232876712
2014 7.69260273972603
2013 10.6446575342466
2012 8.20054644808743
2011 11.286301369863
2010 10.8293150684932
2009 6.70027397260274
2008 8.08005464480874
2007 7.10027397260274
2006 8.03972602739726
2005 10.1183561643836
2004 10.5125683060109
2003 6.45506849315068
2002 7.12493150684931
2001 6.81945205479452