2017 4.86849315068493
2016 5.52814207650273
2015 3.86356164383562
2014 3.73205479452055
2013 5.47945205479452
2012 5.22459016393443
2011 7.17397260273973
2010 5.69890410958904
2009 4.44246575342466
2008 3.84565916398714
2007 3.77598253275109
2006 3.45041095890411
2005 5.47452054794521
2004 6.99071038251366
2003 4.60828402366864
2002 4.24383561643836
2001 3.71068493150685