Year	Number
1996	0.47480720281601
1998	0.435220897197723
2000	0.453906059265137
2002	0.436297506093979
2003	0.349641561508179
2004	0.364736646413803
2005	0.384340941905975
2006	0.376439899206162
2007	0.348420560359955
2008	0.350017130374908
2009	0.323601871728897
2010	0.320087254047394
2011	0.360775291919708
2012	0.282746523618698
2013	0.297252923250198
2014	0.238057717680931
2015	0.249322980642319
2016	0.246931627392769
2017	0.256252259016037
2018	0.250291615724564
2019	0.271939843893051
2020	0.27869239449501
2021	0.282457619905472
2022	0.277728617191315