Year	Number
1996	-1.42548000812531
1998	-1.58477294445038
2000	-1.63516211509705
2002	-1.64862954616547
2003	-1.78975963592529
2004	-1.78558814525604
2005	-1.8051575422287
2006	-1.88721024990082
2007	-1.85398316383362
2008	-1.80063891410828
2009	-1.70388305187225
2010	-1.61688709259033
2011	-1.61035680770874
2012	-1.51460742950439
2013	-1.4786741733551
2014	-1.54479646682739
2015	-1.55811536312103
2016	-1.56008720397949
2017	-1.55243134498596
2018	-1.45681869983673
2019	-1.44007456302643
2020	-1.41953611373901
2021	-1.42282140254974
2022	-1.33949506282806
