Year	Number
1996	20.5
1998	25.8706474304199
2000	30.8457717895508
2002	28.3582096099854
2003	29.8507461547852
2004	25.9615383148193
2005	25.9615383148193
2006	31.25
2007	32.6923065185547
2008	32.211540222168
2009	32.2274894714355
2010	33.6492881774902
2011	31.9248828887939
2012	31.9248828887939
2013	34.2723007202148
2014	30.5418720245361
2015	35.9605903625488
2016	40.3940887451172
2017	41.8719215393066
2018	36.4077682495117
2019	34.2995185852051
2020	34.7826080322266
2021	36.2318840026855
2022	25.1207733154297