Year	Number
1996	-1.16929292678833
1998	-0.849191963672638
2000	-0.87711489200592
2002	-0.95980703830719
2003	-0.768268346786499
2004	-0.905938565731049
2005	-1.06517994403839
2006	-1.27254664897919
2007	-1.25723922252655
2008	-1.183345079422
2009	-1.04185616970062
2010	-1.12180197238922
2011	-1.14293134212494
2012	-1.25816690921783
2013	-1.1697952747345
2014	-1.23705840110779
2015	-1.18450438976288
2016	-1.06488299369812
2017	-1.08643198013306
2018	-1.02534222602844
2019	-0.855753898620605
2020	-0.969850122928619
2021	-0.953995585441589
2022	-0.941579163074493