Year	Number of
2000	31000
2001	30000
2002	29000
2003	28000
2004	28000
2005	26000
2006	26000
2007	26000
2008	24000
2009	23000
2010	22000
2011	21000
2012	20000
2013	19000
2014	18000
2015	18000
2016	18000
2017	18000
2018	17000
2019	17000
2020	16000