Year	Number of
1990	9676
1991	10160
1992	10680
1993	11240
1994	11800
1995	12360
1996	12900
1997	13440
1998	13990
1999	14560
2000	15190
2001	15880
2002	16630
2003	17430
2004	18280
2005	19160
2006	20080
2007	21040