Year	Number
1996	-0.972584128379822
1998	-1.20082128047943
2000	-1.00120759010315
2002	-1.21066498756409
2003	-1.50999701023102
2004	-1.28043293952942
2005	-1.01388049125671
2006	-1.06518423557281
2007	-1.15429580211639
2008	-1.10970735549927
2009	-1.35554790496826
2010	-1.27798449993134
2011	-1.32679533958435
2012	-1.28930985927582
2013	-1.22917413711548
2014	-0.997911989688873
2015	-0.954773545265198
2016	-0.960426509380341
2017	-0.774099051952362
2018	-0.997705161571503
2019	-0.796840608119965
2020	-0.841136157512665
2021	-0.691997945308685
2022	-0.568608164787292