diff --git a/notes_tools/tools/df_marks_manip.py b/notes_tools/tools/df_marks_manip.py
index 845bddd..eb3b193 100644
--- a/notes_tools/tools/df_marks_manip.py
+++ b/notes_tools/tools/df_marks_manip.py
@@ -116,6 +116,9 @@ def note_to_level(x):
     if pd.isnull(x["Note"]):
         return "na"
 
+    if pd.isnull(x["Bareme"]) or x["Bareme"] == 0:
+        return "na"
+
     if x["Niveau"]:
         return int(x["Note"])
     else: