Year	Number of
1990	46910
1991	43450
1992	21420
1993	12540
1994	13730
1995	16370
1996	18860
1997	22400
1998	21860
1999	19090
2000	29740
2001	29490
2002	29490
2003	31720
2004	46660
2005	45050
2006	37060