1970	  44
1971	  37
1973	   2
1974	   2
1977	   1
1978	   2
1979	   1
1980	   1
1981	   5
1982	   3
1983	   2
1984	 508
1985	 966
1986	 978
1987	1045
1988	1006
1989	1071
1990	1255
1991	 155