Year	Number
1996	16.5
1998	13.4328355789185
2000	13.4328355789185
2002	13.4328355789185
2003	14.4278602600098
2004	15.865385055542
2005	13.4615383148193
2006	8.17307662963867
2007	8.65384578704834
2008	9.61538505554199
2009	18.9573459625244
2010	21.8009471893311
2011	24.8826293945313
2012	25.3521118164063
2013	25.8215961456299
2014	21.674877166748
2015	20.6896553039551
2016	14.7783250808716
2017	14.2857141494751
2018	17.4757289886475
2019	14.4927539825439
2020	15.4589376449585
2021	18.8405799865723
2022	18.8405799865723