Year	Number
2006	11796
2007	19241
2008	19300
2009	14073
2010	13750
2011	14595
2012	12938
2013	14093
2014	12790
2015	12508
2016	12952
2017	13008
2018	12989
2019	13064
2020	12904
2021	13759