Year Number 1996 0.539628803730011 1998 0.509335398674011 2000 0.57901805639267 2002 0.386922985315323 2003 0.153711155056953 2004 0.06238729134202 2005 -0.00755707500502467 2006 -0.0693550705909729 2007 -0.137440487742424 2008 -0.159740418195724 2009 -0.260052651166916 2010 -0.233622625470161 2011 -0.229752525687218 2012 -0.172369107604027 2013 -0.139015212655067 2014 -0.220252081751823 2015 -0.188147738575935 2016 -0.0281623397022486 2017 0.0136582739651203 2018 -0.00407756073400378 2019 0.0885664150118828 2020 0.109724149107933 2021 0.0948904007673264 2022 0.067307785153389