Year	Number of
1990	11370
1991	11730
1992	12100
1993	12480
1994	12860
1995	13240
1996	14230
1997	14480
1998	14830
1999	15330
2000	15880
2001	16500
2002	17210
2003	17990
2004	14250
2005	16730
2006	16910
2007	17470