diff --git a/b2/dump.c b/b2/dump.c
index 475c226..31d3f8b 100644
--- a/b2/dump.c
+++ b/b2/dump.c
@@ -50,7 +50,7 @@ void dump_abs(FILE *file, const struct format *fmt, const struct value *v)
 void dump_rel(FILE *file, const struct format *fmt, const struct value *v)
 {
 	if (v->u.rel.fract)
-		fprintf(file, "-%f/+%f%%",
+		fprintf(file, "-%g/+%g%%",
 		    v->u.rel.minus*100, v->u.rel.plus*100);
 	else
 		fprintf(file, "-%g/+%g%s",