Year Number 1996 -1.77829897403717 1998 -1.48284018039703 2000 -1.90411269664764 2002 -0.777628898620605 2003 -0.833158433437347 2004 -1.01044058799744 2005 -1.15223681926727 2006 -1.42155075073242 2007 -1.75128364562988 2008 -1.79859554767609 2009 -1.34090304374695 2010 -0.94294685125351 2011 -0.724771440029144 2012 -0.717079222202301 2013 -0.612895429134369 2014 -0.330464035272598 2015 0.0831826627254486 2016 -0.0113400500267744 2017 -0.0754485204815865 2018 -0.139389723539352 2019 -0.21556980907917 2020 -0.0891569182276726 2021 -0.376803755760193 2022 -0.785569846630096