Year	Number of
1990	22680
1991	42200
1992	39700
1993	33170
1994	39570
1995	59310
1997	32100
1998	41200
1999	27280
2000	24020
2001	27120
2002	21900
2003	27630
2004	28870
2005	38980
2006	21000