Year	Number
1996	-1.05334162712097
1998	-0.95437353849411
2000	-0.943414032459259
2002	-0.954848229885101
2003	-0.783091723918915
2004	-0.825626492500305
2005	-0.847120821475983
2006	-0.940847754478455
2007	-1.01758086681366
2008	-1.12522864341736
2009	-1.14130687713623
2010	-1.09921479225159
2011	-1.07437682151794
2012	-1.05157160758972
2013	-1.02038681507111
2014	-0.918525218963623
2015	-0.973685264587402
2016	-0.838142871856689
2017	-0.91401869058609
2018	-0.86911803483963
2019	-0.821954846382141
2020	-0.929947912693024
2021	-0.920365571975708
2022	-0.97938734292984