Year	Number
1996	-1.12103068828583
1998	-1.02284121513367
2000	-0.906228959560394
2002	-0.981288135051727
2003	-1.04470455646515
2004	-1.05670249462128
2005	-1.12416350841522
2006	-1.27916121482849
2007	-1.23339664936066
2008	-1.32513201236725
2009	-1.25976669788361
2010	-1.30459702014923
2011	-1.30184757709503
2012	-1.29948163032532
2013	-1.4027693271637
2014	-1.47917592525482
2015	-1.55238330364227
2016	-1.56097424030304
2017	-1.56363570690155
2018	-1.50821161270142
2019	-1.52881360054016
2020	-1.5415164232254
2021	-1.52770555019379
2022	-1.4408358335495