diff --git a/src/tbf_dl.cpp b/src/tbf_dl.cpp
index fa1b8ac..3f2ef22 100644
--- a/src/tbf_dl.cpp
+++ b/src/tbf_dl.cpp
@@ -726,7 +726,7 @@
 		name(), m_window.v_a(), m_window.v_s(), lost, received,
 		skipped, bsn, info);
 
-	if (lost + received == 0)
+	if (lost + received <= 1)
 		return -1;
 
 	return lost * 100 / (lost + received);