Year	Number
1996	13
1998	14.9253730773926
2000	17.412935256958
2002	10.945273399353
2003	6.46766185760498
2004	5.28846168518066
2005	10.0961542129517
2006	12.0192308425903
2007	10.0961542129517
2008	12.9807691574097
2009	13.2701425552368
2010	12.3222751617432
2011	12.2065725326538
2012	7.51173686981201
2013	3.75586843490601
2014	5.41871929168701
2015	8.86699485778809
2016	12.8078813552856
2017	12.3152713775635
2018	10.1941747665405
2019	9.17874431610107
2020	6.7632851600647
2021	11.5942029953003
2022	9.66183567047119