Year Number 1996 -0.54373174905777 1998 -0.683049440383911 2000 -1.30195045471191 2002 -1.0568835735321 2003 -1.29919517040253 2004 -1.45551669597626 2005 -1.95789563655853 2006 -1.78465950489044 2007 -1.36203336715698 2008 -1.20710647106171 2009 -0.950552523136139 2010 -0.720438122749329 2011 -0.599719345569611 2012 -0.518739342689514 2013 -0.536078989505768 2014 -0.273108631372452 2015 -0.374532461166382 2016 -0.280753701925278 2017 -0.244979038834572 2018 -0.304469525814056 2019 -0.296665459871292 2020 -0.436710476875305 2021 -0.252974152565002 2022 -0.196214869618416