Year	Number
1996	14.2076501846313
1998	16.9398899078369
2000	19.1256828308105
2002	15.6756753921509
2003	13.5135135650635
2004	12.93532371521
2005	15.6862745285034
2006	18.0487804412842
2007	18.4466018676758
2008	16.990291595459
2009	14.8325357437134
2010	17.7033500671387
2011	21.8009471893311
2012	15.1658763885498
2013	14.6919431686401
2014	12.9807691574097
2015	10
2016	11.9047622680664
2017	18.5714282989502
2018	16.1904754638672
2019	14.2857141494751
2020	12.380952835083
2021	10.9523811340332
2022	9.90566062927246