Year	Number
1996	14.5
1998	13.4328355789185
2000	11.9402980804443
2002	10.945273399353
2003	9.95024871826172
2004	8.17307662963867
2005	8.17307662963867
2006	6.73076915740967
2007	6.73076915740967
2008	5.76923084259033
2009	6.63507127761841
2010	6.16113758087158
2011	5.16431903839111
2012	3.75586843490601
2013	3.75586843490601
2014	4.43349742889404
2015	4.43349742889404
2016	4.92610836029053
2017	4.43349742889404
2018	5.82524251937866
2019	4.8309178352356
2020	5.31400966644287
2021	8.21256065368652
2022	8.69565200805664