Year Number 1996 20.4301071166992 1998 24.0641708374023 2000 24.4680843353271 2002 21.6931209564209 2003 20.6349201202393 2004 19.7044334411621 2005 17.5609760284424 2006 14.1463413238525 2007 14.5631065368652 2008 17.9611644744873 2009 8.61244010925293 2010 5.7142858505249 2011 7.5829381942749 2012 3.3175356388092 2013 1.42180097103119 2014 2.88461542129517 2015 0.952380955219269 2016 2.85714292526245 2017 3.33333325386047 2018 3.33333325386047 2019 2.38095235824585 2020 2.85714292526245 2021 3.80952382087708 2022 3.77358484268188