diff --git a/salt_observer/models.py b/salt_observer/models.py
index 9bf894acd86bc96cde773f566de2a7d8cba636dc..58cb7d6c75dbd36bee4aee23797ef6732ac98334 100644
--- a/salt_observer/models.py
+++ b/salt_observer/models.py
@@ -125,7 +125,7 @@ class Minion(MarkdownContent):
     def fullest_partition_percentage(self):
         try:
             return max([p.get('percent', 0) for p in self.data.get('mounted_devices', [])])
-        except AttributeError:
+        except (AttributeError, ValueError):
             return 0
 
     def __str__(self):