Year	Number
1996	-1.44708013534546
1998	-1.39176893234253
2000	-1.38917946815491
2002	-1.0802047252655
2003	-1.15406620502472
2004	-1.30232226848602
2005	-1.42345333099365
2006	-1.42099547386169
2007	-1.45206928253174
2008	-1.54027628898621
2009	-1.55229949951172
2010	-1.48563277721405
2011	-1.44817268848419
2012	-1.39905977249146
2013	-1.38307952880859
2014	-1.36753964424133
2015	-1.18703675270081
2016	-1.24308574199677
2017	-1.25483393669128
2018	-1.23089265823364
2019	-1.23839044570923
2020	-1.30276215076447
2021	-1.16071748733521
2022	-1.10235893726349