Year Number 1996 11.557788848877 1998 12 2000 14.9253730773926 2002 14.4278602600098 2003 4.47761201858521 2004 7.692307472229 2005 4.78468894958496 2006 2.87081336975098 2007 4.30622005462646 2008 2.4038462638855 2009 3.79146909713745 2010 3.3175356388092 2011 2.81690144538879 2012 3.28638505935669 2013 5.16431903839111 2014 9.61538505554199 2015 8.5714282989502 2016 7.14285707473755 2017 8.5714282989502 2018 7.14285707473755 2019 6.66666650772095 2020 7.14285707473755 2021 7.61904764175415 2022 8.01886749267578