Year	Number of
1990	15370
1991	17140
1992	18380
1993	19720
1994	21040
1995	22490
1996	26150
1997	31180
1998	34160
1999	31830
2000	35540
2001	39530
2002	45780
2003	54280
2004	53750
2005	52570
2006	52860
2007	53620