Year	Number of
1990	0
1991	0
1992	0
1993	0
1994	0
1995	0
1996	0
1997	26
1998	207
1999	1338
2000	4196
2001	6465
2002	7910
2003	9417
2004	11000
2005	12610
2006	14290
2007	16000