Year	Number of
1990	16620
1991	16450
1992	16260
1993	16070
1994	15860
1995	15650
1996	15430
1997	15210
1998	14980
1999	14750
2000	14510
2001	14260
2002	14020
2003	13770
2004	13530
2005	13300
2006	13080
2007	12860