Year	Number
2000	15000
2001	14000
2002	14000
2003	15000
2004	14000
2005	13000
2006	14000
2007	14000
2008	14000
2009	14000
2010	14000
2011	15000
2012	15000
2013	15000
2014	15000
2015	15000
2016	16000
2017	16000
2018	16000
2019	18000
2020	19000