Year	Number
1996	-2.41730952262878
1998	-2.42735457420349
2000	-2.43896889686584
2002	-2.03503370285034
2003	-2.19837236404419
2004	-2.29568219184875
2005	-2.06750988960266
2006	-2.21913456916809
2007	-2.4133734703064
2008	-2.69136095046997
2009	-2.71142148971558
2010	-2.57915186882019
2011	-2.50205969810486
2012	-2.41856145858765
2013	-2.51934909820557
2014	-2.41106843948364
2015	-2.56262516975403
2016	-2.6621561050415
2017	-2.79497361183167
2018	-2.75326204299927
2019	-2.65240693092346
2020	-2.70263171195984
2021	-2.51853036880493
2022	-2.5508017539978