Year	Number of
1990	23300
1991	22020
1992	22030
1993	25880
1994	26030
1995	27350
1996	26000
1997	28830
1998	31060
1999	32770
2000	34380
2001	37000
2002	36610
2003	39180
2004	39090
2005	38190
2006	36090
2007	38440