Year	Number
1996	-1.43762958049774
1998	-1.63000500202179
2000	-1.64677035808563
2002	-1.48651361465454
2003	-1.43353641033173
2004	-1.55832588672638
2005	-1.46834909915924
2006	-1.50492835044861
2007	-1.45251274108887
2008	-1.44569098949432
2009	-1.47102332115173
2010	-1.54846596717834
2011	-1.48733866214752
2012	-1.60031580924988
2013	-1.54353320598602
2014	-1.46566355228424
2015	-1.48868584632874
2016	-1.55810081958771
2017	-1.57519114017487
2018	-1.65524923801422
2019	-1.69174087047577
2020	-1.71425592899323
2021	-1.73251974582672
2022	-1.49326610565186