Year Number 1996 0.753051400184631 1998 0.90372896194458 2000 0.868542313575745 2002 1.06869447231293 2003 0.595756590366364 2004 0.631576538085938 2005 0.708228170871735 2006 0.736050128936768 2007 0.582772672176361 2008 0.359765231609344 2009 0.587060391902924 2010 0.691537201404572 2011 0.508276045322418 2012 0.638402462005615 2013 0.677918016910553 2014 0.577418208122253 2015 0.669974029064178 2016 0.648553013801575 2017 0.597006142139435 2018 0.453240990638733 2019 0.43024280667305 2020 0.746752381324768 2021 0.860289990901947 2022 0.954446792602539