Year	Number
1996	-1.11013698577881
1998	-1.25820994377136
2000	-1.11060929298401
2002	-1.09139394760132
2003	-0.966655313968658
2004	-0.979341566562653
2005	-0.740642905235291
2006	-0.772781848907471
2007	-0.820174932479858
2008	-0.862514138221741
2009	-1.07173681259155
2010	-1.03196251392365
2011	-1.0867133140564
2012	-1.11753916740417
2013	-1.17626178264618
2014	-1.02434241771698
2015	-1.03894805908203
2016	-0.866792738437653
2017	-0.831375658512115
2018	-0.921201884746552
2019	-0.800242602825165
2020	-0.831856071949005
2021	-0.786468088626862
2022	-0.633566200733185