Year	Number
1996	-0.844184160232544
1998	-0.911786079406738
2000	-0.89450615644455
2002	-1.10229003429413
2003	-1.08318543434143
2004	-0.947557926177979
2005	-0.964780926704407
2006	-1.19926512241364
2007	-1.16774547100067
2008	-1.21223938465118
2009	-1.15747153759003
2010	-1.18803703784943
2011	-1.13998341560364
2012	-0.765063405036926
2013	-1.05155897140503
2014	-1.17993485927582
2015	-1.18993127346039
2016	-1.20455706119537
2017	-1.251300573349
2018	-1.32480442523956
2019	-1.44390308856964
2020	-1.483353972435
2021	-1.50708985328674
2022	-1.45158803462982