Year	Number
1980	43538
1981	18652
1982	18968
1983	46550
1984	52553
1985	50154
1986	50544
1987	57050
1988	58618
1989	65040
1990	66289
1991	64338
1992	67839
1993	68986
1994	73315
1995	95697
1996	120654
1997	130334
1998	158860
1999	158949
2000	165812
2001	177322
2002	177544
2003	187296
2004	214057
2005	243863
2006	260213
2007	270387
2008	271616
2009	239908
2010	256608
2011	276525
2012	282856
2013	301273
2014	312965
2015	322725
2016	320907
2017	321721
2018	345379
2019	361970
2020	354833