2017 6.23095890410959
2016 7.0103825136612
2015 5.68767123287671
2014 5.39616438356164
2013 8.47232876712329
2012 7.25846994535519
2011 8.2427397260274
2010 8.14794520547945
2009 6.37150684931507
2008 7.09090909090909
2007 3.63666666666667
2006 6.80684931506849
2005 7.59369863013699
2004 10.951912568306
2003 5.81041095890411
2002 5.73917808219178
2001 6.61369863013699