diff --git a/souffle/sgff.dl b/souffle/sgff.dl
index 527e3d13cf559bba5dab460a5c67756c5da524c1..cc3504dbf90e2bac30d36cd6e5ebf368e365ef18 100644
--- a/souffle/sgff.dl
+++ b/souffle/sgff.dl
@@ -12,7 +12,7 @@
 //
 
 //.decl sg (n:number, m:number) output
-.decl sg (n:number, m:number)
+.decl sg (n:number, m:number) eqrel
 //.output sg(IO=stdout)
 .printsize sg