Year	Number
1996	17.3913040161133
1998	16.8478260040283
2000	16.3043479919434
2002	14.5945949554443
2003	18.9189186096191
2004	20.8955230712891
2005	24.5098037719727
2006	25
2007	22.3300971984863
2008	21.3592224121094
2009	24.8803825378418
2010	26.3157901763916
2011	26.0663509368896
2012	27.488151550293
2013	28.9099521636963
2014	28.365385055542
2015	27.1428565979004
2016	23.8095245361328
2017	16.6666660308838
2018	15.2380952835083
2019	15.2380952835083
2020	14.7619047164917
2021	17.619047164917
2022	20.2830181121826