Year	Number of
1990	7187
1991	9671
1992	12320
1993	14400
1994	16030
1995	17350
1996	18480
1997	19700
1998	20460
1999	21590
2000	21760
2001	23890
2002	13220
2003	11980
2004	12060
2005	12400
2006	11640
2007	10620