Year	Number
1996	-1.48739111423492
1998	-1.41050136089325
2000	-1.3698582649231
2002	-1.42397999763489
2003	-1.31896460056305
2004	-1.62806761264801
2005	-1.61142349243164
2006	-1.64104187488556
2007	-1.56595134735107
2008	-1.45997738838196
2009	-1.45370447635651
2010	-1.47331619262695
2011	-1.43329453468323
2012	-1.3807088136673
2013	-1.3615380525589
2014	-1.34434604644775
2015	-1.41903162002563
2016	-1.48770534992218
2017	-1.47983813285828
2018	-1.46416521072388
2019	-1.40951299667358
2020	-1.39946234226227
2021	-1.4585075378418
2022	-1.49223685264587