Year	Number
1996	20.1086959838867
1998	17.9347820281982
2000	15.2173910140991
2002	18.9189186096191
2003	18.9189186096191
2004	18.9054718017578
2005	18.6274509429932
2006	21.0784320831299
2007	22.3300971984863
2008	21.3592224121094
2009	23.9234447479248
2010	22.9665069580078
2011	22.274881362915
2012	27.962085723877
2013	25.1184825897217
2014	32.6923065185547
2015	34.2857131958008
2016	28.5714282989502
2017	27.619047164917
2018	35.238094329834
2019	33.3333320617676
2020	36.1904754638672
2021	39.523811340332
2022	42.4528312683105