Year	Number
1996	16
1998	10.4477615356445
2000	12.4378108978271
2002	8.95522403717041
2003	8.4577112197876
2004	9.13461494445801
2005	8.65384578704834
2006	7.692307472229
2007	8.17307662963867
2008	8.17307662963867
2009	8.05687236785889
2010	7.5829381942749
2011	8.45070457458496
2012	8.92018795013428
2013	10.7981224060059
2014	9.35960578918457
2015	10.3448276519775
2016	10.3448276519775
2017	10.3448276519775
2018	8.25242710113525
2019	11.5942029953003
2020	11.5942029953003
2021	13.043478012085
2022	13.5265703201294