Year	Number
1997	544926
1998	354320
1999	301856
2000	366732
2001	315781
2002	314374
2003	313524
2004	306512
2005	306469
2006	292352
2007	207730
2008	189675
2009	179771
2010	160742
2011	165109
2012	155687
2013	192707
2014	217306
2015	213465
2016	237642
2017	259904
2018	363586