Year	Number
1996	0.187617555260658
1998	0.302315533161163
2000	0.331546425819397
2002	0.295856952667236
2003	0.361106097698212
2004	0.376263976097107
2005	0.296854168176651
2006	0.318718701601028
2007	0.319038897752762
2008	0.310113310813904
2009	0.298496216535568
2010	0.274219661951065
2011	0.269618809223175
2012	0.254466712474823
2013	0.213398680090904
2014	0.231426030397415
2015	0.22516342997551
2016	0.24264220893383
2017	0.252086043357849
2018	0.234587639570236
2019	0.245334640145302
2020	0.265618830919266
2021	0.257541805505753
2022	0.2500921189785