Year	Number
1981	1211
1982	1369
1983	1267
1984	936
1985	1917
1988	1556
1989	3897
1992	5296
1993	5958
2000	5949
2001	6004
2002	5838
2003	6877
2004	8158
2005	8890
2006	8434
2007	9363
2008	11526
2009	10904
2010	13140