Year	Number of
1990	5671
1991	9499
1992	14050
1993	18650
1994	22880
1995	25910
1996	27360
1997	29460
1998	31450
1999	32950
2000	34520
2001	34540
2002	35470
2003	35720
2004	36000
2005	35490
2006	34180
2007	32790