Year	Number of
1980	8
1981	3
1982	0
1983	1
1984	3
1985	2
1986	7
1987	0
1988	3
1989	3
1990	1
1991	0
1992	6
1995	0
1996	3
1997	4
1998	4
1999	3
2000	4
2001	1
2002	4
2003	1
2005	6
2006	4
2007	2