Year	Number
2000	3100
2001	3000
2002	2800
2003	3000
2004	2300
2005	2400
2006	2700
2007	2600
2008	2400
2009	2200
2010	2000
2011	2000
2012	1900
2013	1800
2014	1700
2015	1600
2016	1500
2017	1500
2018	1200
2019	1200
2020	790