Year	Number
1996	-2.47953200340271
1998	-2.25996828079224
2000	-2.24417304992676
2002	-1.846431016922
2003	-1.97705578804016
2004	-1.54903697967529
2005	-1.97329592704773
2006	-2.13907742500305
2007	-2.36272478103638
2008	-2.48534822463989
2009	-2.64707374572754
2010	-2.66527771949768
2011	-2.5229172706604
2012	-2.26056337356567
2013	-2.19300961494446
2014	-2.36308455467224
2015	-2.15515303611755
2016	-2.33110570907593
2017	-1.97152423858643
2018	-1.82177793979645
2019	-1.69619822502136
2020	-1.65706396102905
2021	-1.98757219314575
2022	-1.99889421463013