Year	Number of
1990	12780
1991	17560
1992	22850
1993	27300
1994	31060
1995	34380
1996	36580
1997	39000
1998	40500
1999	42870
2000	43680
2001	46390
2002	47590
2003	50010
2004	48580
2005	46680
2006	44280
2007	41950