Year	Number
1996	-1.77677261829376
1998	-2.02131986618042
2000	-2.24290561676025
2002	-1.51051068305969
2003	-1.4239000082016
2004	-1.58119010925293
2005	-1.51382398605347
2006	-1.62845742702484
2007	-1.50605273246765
2008	-1.36384046077728
2009	-1.46917331218719
2010	-1.5364773273468
2011	-1.55778133869171
2012	-1.5799834728241
2013	-1.60398280620575
2014	-1.72982561588287
2015	-1.6880589723587
2016	-1.63551414012909
2017	-1.2975754737854
2018	-1.13866889476776
2019	-1.05532276630402
2020	-0.999216437339783
2021	-0.595436334609985
2022	-0.55031543970108