Year	Number
1996	-0.99362987279892
1998	-0.97202205657959
2000	-0.978057503700256
2002	-0.940512537956238
2003	-1.10341620445251
2004	-1.23052859306335
2005	-1.3077164888382
2006	-1.4184205532074
2007	-1.45132219791412
2008	-1.44590663909912
2009	-1.39856195449829
2010	-1.36032783985138
2011	-1.35003161430359
2012	-1.34274756908417
2013	-1.37470948696136
2014	-1.3308037519455
2015	-1.33509016036987
2016	-1.36274147033691
2017	-1.37138092517853
2018	-1.46489036083221
2019	-1.43428111076355
2020	-1.40318298339844
2021	-1.41787803173065
2022	-1.47625410556793