Year	Number of
1990	744
1991	1084
1992	1512
1993	2090
1994	2813
1995	3702
1996	4772
1997	6147
1998	7740
1999	9544
2000	11660
2001	13870
2002	15590
2003	17010
2004	17860
2005	18150
2006	17960
2007	17480