2017 24.3635616438356
2016 24.4762295081967
2015 24.4175342465753
2014 24.1964383561644
2013 24.2145205479452
2012 24.505737704918
2011 24.18
2010 24.7027397260274
2009 24.5367123287671
2008 24.3142076502732
2007 24.7282191780822
2006 24.7293150684932
2005 24.6490410958904
2004 24.3718579234973
2003 24.5964383561644
2002 24.4331506849315
2001 24.4375342465753