Year	Number of
1980	9877
1981	10840
1982	10950
1983	10210
1984	11440
1985	14940
1986	14070
1987	19720
1988	25700
1989	13340
1990	20120
1991	19630
1992	14800
1993	11600
1994	8449
1995	13420
1996	15020
1997	16660
1998	20250
1999	24160
2000	25820
2001	45840
2002	38630
2003	44180
2004	57250
2005	62600
2006	70730
2007	82420