Year	Number
1992	23500
1993	20000
1994	18200
1995	16600
1996	16600
1997	12000
1998	17240
1999	18147
2000	17199
2001	17838
2002	21860
2003	18500
2004	15096
2005	17600
2006	20000
2007	27500