Year	Number of
2000	18000
2001	15000
2002	14000
2003	15000
2004	15000
2005	17000
2006	19000
2007	19000
2008	19000
2009	13000
2010	9200
2011	10000
2012	9900
2013	7100
2014	7100
2015	5900
2016	5400
2017	5000
2018	4600
2019	6300
2020	8000