Year	Number
1996	19.680850982666
1998	18.6170215606689
2000	19.0476188659668
2002	12.6984128952026
2003	5.52763795852661
2004	4.85436916351318
2005	5.33980560302734
2006	5.31400966644287
2007	9.17874431610107
2008	15.865385055542
2009	14.6919431686401
2010	9.00473976135254
2011	5.68720388412476
2012	10.4265403747559
2013	9.47867298126221
2014	10
2015	9.5238094329834
2016	13.8095235824585
2017	20.4761905670166
2018	16.0377349853516
2019	22.6415100097656
2020	18.3962268829346
2021	18.3962268829346
2022	15.5660381317139