Year	Number
1996	-1.24000644683838
1998	-1.11979472637177
2000	-1.01888477802277
2002	-1.03582286834717
2003	-1.17005813121796
2004	-1.2469025850296
2005	-1.38764119148254
2006	-1.19128274917603
2007	-1.32981109619141
2008	-1.42751383781433
2009	-1.15030837059021
2010	-1.19666075706482
2011	-1.20462548732758
2012	-1.50337672233582
2013	-1.48882293701172
2014	-1.46264123916626
2015	-1.49990391731262
2016	-1.56056940555573
2017	-1.56021547317505
2018	-1.45669090747833
2019	-1.40784466266632
2020	-1.42334496974945
2021	-1.27922034263611
2022	-1.39786016941071