Year Number 1996 0.644922494888306 1998 0.65214592218399 2000 0.872710645198822 2002 0.834610283374786 2003 0.834165394306183 2004 0.623478174209595 2005 0.570550501346588 2006 0.567707121372223 2007 0.593567669391632 2008 0.629704236984253 2009 0.670539855957031 2010 0.680927038192749 2011 0.674052000045776 2012 0.750935077667236 2013 0.792424201965332 2014 0.159695938229561 2015 0.213033154606819 2016 0.166600421071053 2017 -0.241829127073288 2018 -0.269048988819122 2019 -0.253151446580887 2020 -0.126706585288048 2021 -0.120851926505566 2022 -0.0970938131213188