Year	Number of
1990	71670
1991	59400
1992	41090
1993	46860
1994	30010
1995	18130
1996	11880
1997	16360
1998	43700
1999	87620
2000	98600
2001	108900
2002	86760
2003	52060
2004	28730
2005	17050
2006	9863