Year	Number
1996	-1.37976360321045
1998	-1.39227020740509
2000	-1.45724165439606
2002	-1.47391068935394
2003	-1.2604101896286
2004	-1.23347663879395
2005	-1.26733553409576
2006	-1.03928434848785
2007	-0.969070315361023
2008	-0.984243035316467
2009	-1.0932948589325
2010	-1.09233939647675
2011	-1.29189229011536
2012	-1.27767753601074
2013	-1.1865621805191
2014	-1.19583749771118
2015	-1.28828191757202
2016	-1.6733832359314
2017	-1.76530337333679
2018	-1.80685091018677
2019	-1.79067075252533
2020	-1.77609324455261
2021	-1.80289542675018
2022	-1.84966695308685