Year	Number
1996	0.39190337061882
1998	0.308850228786469
2000	0.418346971273422
2002	0.260062754154205
2003	0.349125266075134
2004	0.362040877342224
2005	0.269231617450714
2006	0.403436541557312
2007	0.448621332645416
2008	0.358895927667618
2009	0.280091494321823
2010	0.361670136451721
2011	0.344941824674606
2012	0.295209914445877
2013	0.276987880468369
2014	0.345339059829712
2015	0.411802023649216
2016	0.493365466594696
2017	0.528666615486145
2018	0.539418399333954
2019	0.571178674697876
2020	0.585294365882874
2021	0.611695528030396
2022	0.543526768684387