Year	Number
1996	-1.15238130092621
1998	-1.1665472984314
2000	-1.37595665454865
2002	-0.955280721187592
2003	-1.4330381155014
2004	-1.56201231479645
2005	-1.45132994651794
2006	-1.54490375518799
2007	-1.57391834259033
2008	-1.43187046051025
2009	-1.32386815547943
2010	-1.31199896335602
2011	-1.30544543266296
2012	-1.43880379199982
2013	-1.80894291400909
2014	-1.70606768131256
2015	-1.71096646785736
2016	-1.85057771205902
2017	-1.76183152198792
2018	-1.71663010120392
2019	-1.76445817947388
2020	-1.75173819065094
2021	-1.68893265724182
2022	-1.70115745067596