Year	Number of
1990	28130
1991	29760
1992	33280
1993	32300
1994	33680
1995	34140
1996	38550
1997	33530
1998	29290
1999	26720
2000	26140
2001	25660
2002	24970
2003	23860
2004	22260
2005	21220
2006	20270
2007	19530