Year	Number
2000	20000
2001	20000
2002	21000
2003	21000
2004	21000
2005	22000
2006	22000
2007	23000
2008	23000
2009	23000
2010	24000
2011	24000
2012	24000
2013	24000
2014	24000
2015	24000
2016	25000
2017	25000
2018	25000
2019	26000
2020	26000