Year	Number
1996	-0.448235422372818
1998	-0.546766698360443
2000	-0.599425613880157
2002	-0.324264049530029
2003	-0.416089504957199
2004	-0.5878586769104
2005	-0.38015428185463
2006	-0.655422568321228
2007	-0.499808996915817
2008	-0.684332251548767
2009	-0.841211676597595
2010	-0.995213866233826
2011	-1.06907939910889
2012	-1.11727750301361
2013	-1.14704942703247
2014	-1.32189202308655
2015	-1.33112061023712
2016	-1.22790062427521
2017	-1.19547021389008
2018	-1.21207213401794
2019	-1.19329237937927
2020	-1.0527606010437
2021	-1.02771806716919
2022	-0.987728238105774