Year	Number of
2000	2200
2001	2500
2002	2500
2003	2400
2004	2200
2005	1900
2006	1800
2007	1800
2008	1800
2009	1700
2010	1600
2011	1400
2012	1400
2013	1200
2014	1200
2015	1100
2016	1100
2017	1000
2018	990
2019	970
2020	1000