Year	Number
1996	16.3043479919434
1998	20.6521739959717
2000	15.2173910140991
2002	12.972972869873
2003	18.9189186096191
2004	18.9054718017578
2005	17.6470584869385
2006	19.1176471710205
2007	20.8737869262695
2008	22.3300971984863
2009	23.4449768066406
2010	23.4449768066406
2011	26.0663509368896
2012	25.1184825897217
2013	24.1706161499023
2014	25.480770111084
2015	25.238094329834
2016	21.9047622680664
2017	22.8571434020996
2018	21.9047622680664
2019	16.6666660308838
2020	14.7619047164917
2021	19.5238094329834
2022	20.2830181121826