Year	Number
1970	1300
1971	4400
1972	3900
1973	4100
1974	3800
1975	3400
1976	3400
1977	3400
2002	4648
2003	4512
2004	3893
2005	3207
2006	3998
2007	4324
2008	3667
2009	3304
2010	5104.72222222222
2011	7191
2012	7432
2013	11897.0432386171
2014	14732
2015	12983
2016	11933
2017	14372
2018	14387
2019	14850
2020	5639.574
2021	390.662