a user is able to edit other user settings

@@ -70,0 +140,4 @@
+        total = Decimal(sum(current_by_user.values())) / 100
+        history.append((effective_date, total))
+
+    history.reverse()

@@ -566,3 +566,3 @@
     @property
     def working_employees(self) -> Decimal | None:
-        if self.total_production_days is None:
+        if not self.total_production_days:

@@ -50,0 +114,4 @@
+def delete_presence_setting(user, setting):
+    """Delete a presence percentage setting."""
+    if setting.user_id != user.id:
+        abort(404)