Year	Number
1996	-1.25880205631256
1998	-1.48598551750183
2000	-1.67352259159088
2002	-1.40995764732361
2003	-1.15374350547791
2004	-0.984741389751434
2005	-0.899246156215668
2006	-0.850372433662415
2007	-1.06611335277557
2008	-1.09180378913879
2009	-1.2944188117981
2010	-1.28592801094055
2011	-1.11109840869904
2012	-0.943674981594086
2013	-1.14037239551544
2014	-1.08758068084717
2015	-1.16666913032532
2016	-0.808124959468842
2017	-1.08409428596497
2018	-1.26694679260254
2019	-1.33045899868011
2020	-1.51170456409454
2021	-2.08396935462952
2022	-2.21174263954163