Year	Number of
2000	2400
2001	2700
2002	3100
2003	3300
2004	3100
2005	2400
2006	2100
2007	2700
2008	2500
2009	2300
2010	2100
2011	2100
2012	2500
2013	2400
2014	1900
2015	1900
2016	2000
2017	2200
2018	2200
2019	2400
2020	2400