Year Number 1996 -0.339192003011703 1998 -0.964446723461151 2000 -0.241125971078873 2002 -0.313102960586548 2003 -0.91280323266983 2004 -0.344115853309631 2005 -0.812229692935944 2006 -0.262578547000885 2007 -0.123644053936005 2008 0.268389225006104 2009 0.494239002466202 2010 0.253481268882751 2011 0.177703246474266 2012 0.160619214177132 2013 -0.102187521755695 2014 -0.770232260227203 2015 -0.447671920061111 2016 -0.628553986549377 2017 -0.73394501209259 2018 -0.133512377738953 2019 -0.343412548303604 2020 -0.448214262723923 2021 -0.56633985042572 2022 -0.508419454097748