Year	Number
1996	-1.2075936794281
1998	-1.19072878360748
2000	-1.20650112628937
2002	-1.337557554245
2003	-1.29273951053619
2004	-1.5750937461853
2005	-1.53674149513245
2006	-1.47461295127869
2007	-1.49425947666168
2008	-1.54291808605194
2009	-1.6242733001709
2010	-1.62764239311218
2011	-1.60698401927948
2012	-1.47650003433228
2013	-1.50835263729095
2014	-1.29803729057312
2015	-1.28990435600281
2016	-1.01163554191589
2017	-1.08796751499176
2018	-1.09122586250305
2019	-1.18532156944275
2020	-1.01391088962555
2021	-1.41239774227142
2022	-1.68404102325439