Year	Number
1996	-1.49730587005615
1998	-1.67915642261505
2000	-1.68866276741028
2002	-1.82406485080719
2003	-1.7566545009613
2004	-1.79518795013428
2005	-1.85839438438416
2006	-1.98288238048553
2007	-1.95115220546722
2008	-1.94149112701416
2009	-1.91027736663818
2010	-1.94041454792023
2011	-1.59441232681274
2012	-0.900741994380951
2013	-0.97160005569458
2014	-1.11204063892365
2015	-1.33993685245514
2016	-1.42839288711548
2017	-1.44198477268219
2018	-1.53367853164673
2019	-1.47660195827484
2020	-1.35957860946655
2021	-1.46046459674835
2022	-1.38782489299774