Year Number 1996 -0.374195218086243 1998 -0.364895522594452 2000 -0.377791106700897 2002 -0.233312800526619 2003 -0.176545038819313 2004 -0.522410035133362 2005 -0.694694995880127 2006 -0.729944288730621 2007 -0.712738215923309 2008 -0.714707136154175 2009 -0.557290554046631 2010 -0.587572574615479 2011 -0.513804793357849 2012 -0.653231739997864 2013 -0.706011950969696 2014 -0.693982779979706 2015 -0.813672840595245 2016 -0.850145161151886 2017 -0.657365679740906 2018 -0.501664221286774 2019 -0.40828874707222 2020 -0.425882965326309 2021 -0.382034093141556 2022 -0.278427481651306