Year	Number of
1980	4421
1981	4376
1982	4678
1983	4468
1984	4691
1985	4666
1986	4605
1987	4522
1988	4093
1989	4176
1990	4073
1991	3546
1992	600
1993	680
1994	1595
1995	2132
1996	2220
1997	2869
1998	2711
1999	2923
2000	2476
2001	2469
2002	1691
2003	1740
2004	2353
2005	2111
2006	1778
2007	2373