Year	Number
1996	37.5
1998	29.8507461547852
2000	28.3582096099854
2002	41.2935333251953
2003	39.8009948730469
2004	38.461540222168
2005	32.6923065185547
2006	28.8461532592773
2007	29.8076915740967
2008	28.8461532592773
2009	29.8578205108643
2010	27.962085723877
2011	19.2488269805908
2012	15.4929580688477
2013	15.023473739624
2014	19.7044334411621
2015	20.1970443725586
2016	16.2561569213867
2017	15.2709360122681
2018	15.5339803695679
2019	15.9420289993286
2020	14.9758453369141
2021	14.4927539825439
2022	15.9420289993286