Year	Number
1980	429
1981	529
1982	394
1983	482
1984	511
1985	783
1986	960
1987	1037
1988	1106
1989	1274
1990	1354
1991	1443
1992	1349
1993	1549
1994	1613
1995	1779
1996	1334
1997	1637
1998	1736
1999	1750
2000	3762
2001	3553
2002	3946
2003	1670
2004	2642
2005	1567
2006	4298
2007	2561
2008	7777
2009	1962
2010	12466
2011	11481
2012	9814
2013	10664
2014	16603
2015	7248
2016	23594
2017	27168
2018	23224
2019	25934
2020	20948