Year	Number
1996	-0.584048211574554
1998	-0.537716507911682
2000	-0.758916974067688
2002	-1.31789720058441
2003	-1.28644466400146
2004	-1.3915855884552
2005	-1.24433243274689
2006	-1.25286757946014
2007	-1.2296701669693
2008	-1.31243884563446
2009	-1.27778947353363
2010	-1.25623667240143
2011	-1.09404599666595
2012	-1.02713263034821
2013	-1.07763242721558
2014	-0.852002203464508
2015	-0.971670269966125
2016	-1.0229766368866
2017	-1.25151371955872
2018	-1.35144245624542
2019	-1.53918147087097
2020	-1.55198740959167
2021	-1.45388782024384
2022	-1.25646221637726