Year	Number of
1990	32650
1991	33650
1992	35580
1993	35980
1994	37180
1995	37830
1996	37460
1997	34500
1998	33200
1999	30940
2000	29810
2001	28810
2002	28830
2003	29040
2004	28190
2005	28860
2006	29400
2007	29030