Year	Number of
1980	2781
1981	2852
1982	3197
1983	2858
1984	2554
1985	2732
1986	3022
1987	2810
1988	2510
1989	2281
1990	1728
1991	1910
1992	1835
1993	2426
1994	2626
1995	2925
1996	2922
1997	2908
1998	2625
1999	2711
2000	2935
2001	3608
2002	3769
2003	3619
2004	4806
2005	5141
2006	4990
2007	4857