Year Number 1996 0.887499451637268 1998 0.698888778686523 2000 0.785089075565338 2002 0.924183249473572 2003 0.179551064968109 2004 0.345115303993225 2005 0.399723917245865 2006 0.595505774021149 2007 0.563000798225403 2008 0.543759167194366 2009 0.512012898921967 2010 0.681087553501129 2011 0.602992832660675 2012 0.554941534996033 2013 0.448744118213654 2014 0.300568491220474 2015 0.0977598056197166 2016 -0.106349594891071 2017 0.265700727701187 2018 0.0137935001403093 2019 0.271274894475937 2020 0.280948132276535 2021 0.32552382349968 2022 0.334524124860764