Year Number 1996 -0.971613764762878 1998 -0.909501016139984 2000 -0.882966220378876 2002 -0.939510047435761 2003 -0.879082381725311 2004 -0.772796213626862 2005 -0.95474761724472 2006 -0.886092662811279 2007 -0.771052896976471 2008 -0.656676888465881 2009 -0.697536051273346 2010 -0.75210177898407 2011 -0.821726500988007 2012 -0.803623497486115 2013 -0.774326741695404 2014 -0.87566202878952 2015 -0.944647133350372 2016 -1.00065386295319 2017 -0.934071719646454 2018 -0.950232684612274 2019 -0.946248352527618 2020 -1.04289186000824 2021 -1.02881515026093 2022 -1.10204446315765