Year	Number of
2000	1600
2001	1700
2002	1600
2003	1600
2004	1500
2005	1400
2006	1300
2007	1500
2008	1500
2009	1400
2010	1300
2011	1200
2012	1500
2013	1600
2014	1500
2015	1500
2016	1600
2017	1500
2018	1500
2019	1600
2020	2000