Year	Number of
2000	2800
2001	2700
2002	2900
2003	2600
2004	2500
2005	2500
2006	2500
2007	2400
2008	2500
2009	2600
2010	2700
2011	2800
2012	2700
2013	2800
2014	2900
2015	2900
2016	3000
2017	3000
2018	3000
2019	2900
2020	3800