Year	Number
1996	-1.14967966079712
1998	-1.10067796707153
2000	-1.15839385986328
2002	-0.739994645118713
2003	-0.842397630214691
2004	-1.05277228355408
2005	-0.984283983707428
2006	-1.33474802970886
2007	-1.34575927257538
2008	-1.33856463432312
2009	-1.39934432506561
2010	-1.39912748336792
2011	-1.49212002754211
2012	-1.51251459121704
2013	-1.55083477497101
2014	-1.67897701263428
2015	-1.67859208583832
2016	-1.78041470050812
2017	-1.79935944080353
2018	-1.76824188232422
2019	-1.80254232883453
2020	-1.6431565284729
2021	-1.69551146030426
2022	-1.73040449619293