Year	Number of
1981	2265
1982	671
1984	1489
1985	2262
1986	1864
1987	1978
1988	2030
1989	2040
1990	2100
1991	2900
1992	2884
1993	3489
1994	3311
1996	3332
1997	3830
1998	3785
1999	4133
2000	3971
2001	4198
2002	3191
2003	3231
2004	2940
2005	3109
2006	3011
2007	3195