Year Number 1996 -0.336625128984451 1998 -0.544004201889038 2000 -0.539989590644836 2002 -0.297719180583954 2003 -0.309780240058899 2004 -0.427259683609009 2005 -0.505047976970673 2006 -0.508157312870026 2007 -0.203974649310112 2008 -0.0305009130388498 2009 -0.0451405122876167 2010 -0.191482901573181 2011 -0.282379418611526 2012 -0.143631592392921 2013 0.0919297859072685 2014 0.485986232757568 2015 0.341639041900635 2016 0.337447881698608 2017 0.373769819736481 2018 0.366642981767654 2019 0.110049679875374 2020 0.0885764509439468 2021 0.196294024586678 2022 0.114945493638515