Year	Number
1996	-1.78807544708252
1998	-1.73488676548004
2000	-1.78066074848175
2002	-1.67347323894501
2003	-1.5582937002182
2004	-1.6939252614975
2005	-1.66296553611755
2006	-1.87900483608246
2007	-1.85256004333496
2008	-1.90330755710602
2009	-1.87611877918243
2010	-1.87005805969238
2011	-1.9225001335144
2012	-1.6518931388855
2013	-1.60911154747009
2014	-1.43704450130463
2015	-1.51520264148712
2016	-1.52071392536163
2017	-1.58373689651489
2018	-1.68858671188354
2019	-1.74131882190704
2020	-1.83137428760529
2021	-1.87635684013367
2022	-1.65844225883484