Year	Number
1996	17.5879402160645
1998	17
2000	13.4328355789185
2002	12.93532371521
2003	19.4029846191406
2004	18.269229888916
2005	16.7464122772217
2006	25.8373203277588
2007	27.2727279663086
2008	25.480770111084
2009	21.8009471893311
2010	23.222749710083
2011	14.0845069885254
2012	15.4929580688477
2013	17.8403759002686
2014	17.3076915740967
2015	13.3333330154419
2016	8.09523773193359
2017	5.7142858505249
2018	5.2380952835083
2019	5.2380952835083
2020	4.7619047164917
2021	5.2380952835083
2022	5.18867921829224