Year	Number
2000	1500
2001	2100
2002	2000
2003	2000
2004	2100
2005	2000
2006	2000
2007	2000
2008	2000
2009	1900
2010	1900
2011	2000
2012	1900
2013	1800
2014	1800
2015	2100
2016	2300
2017	2300
2018	2200
2019	1600
2020	1400