Year	Number
1996	0.0983566418290138
1998	0.167446434497833
2000	0.0981105268001556
2002	0.0824185758829117
2003	0.0846633911132813
2004	-0.125887230038643
2005	-0.189165323972702
2006	-0.236582726240158
2007	-0.312398791313171
2008	-0.246367320418358
2009	-0.221786111593246
2010	-0.290129393339157
2011	-0.270240843296051
2012	-0.269323468208313
2013	-0.20331783592701
2014	-0.209582656621933
2015	-0.194529786705971
2016	-0.186165526509285
2017	-0.29960623383522
2018	-0.366134911775589
2019	-0.424627780914307
2020	-0.48708176612854
2021	-0.429848790168762
2022	-0.487372189760208