Year	Number
1996	-1.05474293231964
1998	-0.632266759872437
2000	-0.946032106876373
2002	-1.22584557533264
2003	-1.40960443019867
2004	-1.31249165534973
2005	-1.69038331508636
2006	-1.74013221263885
2007	-1.80640935897827
2008	-1.73212063312531
2009	-1.64107227325439
2010	-1.63510119915009
2011	-1.5069637298584
2012	-1.56427133083344
2013	-1.40730738639832
2014	-1.3393874168396
2015	-1.49694204330444
2016	-1.61724519729614
2017	-1.67722964286804
2018	-1.27457964420319
2019	-1.30372190475464
2020	-1.75365614891052
2021	-2.18371319770813
2022	-2.03806757926941