Year	Number
1971	0
1972	0
1973	0
1974	0
1975	0
1976	0
1977	0
1978	0
1979	0
1980	0
1981	0
1982	0
1983	0
1984	0
1985	0
1986	0
1987	126
1988	114
1989	106
1990	113
1991	137
1992	137
1993	158
1994	163
1996	141
1997	129
2000	0
2008	513
2009	521
2010	517
2011	507
2012	538
2018	108