Year	Number
1996	-1.10011386871338
1998	-1.31561851501465
2000	-1.22411334514618
2002	-1.29866790771484
2003	-1.45722651481628
2004	-1.60239171981812
2005	-1.31981468200684
2006	-1.43240511417389
2007	-1.56105935573578
2008	-1.49680125713348
2009	-1.60246276855469
2010	-1.67191302776337
2011	-1.62694549560547
2012	-1.56115961074829
2013	-1.58073723316193
2014	-1.32481598854065
2015	-1.24927258491516
2016	-1.35518074035645
2017	-1.35102510452271
2018	-1.47934222221375
2019	-1.50501537322998
2020	-1.53046345710754
2021	-1.4544278383255
2022	-1.38185942173004