diff --git a/app/models/chargeback/consumption_without_rollups.rb b/app/models/chargeback/consumption_without_rollups.rb
index a0c618d4856..282d84fb39e 100644
--- a/app/models/chargeback/consumption_without_rollups.rb
+++ b/app/models/chargeback/consumption_without_rollups.rb
@@ -50,7 +50,7 @@ def current_value(metric)
                          when 'derived_memory_available'
                            resource.hardware.try(:memory_mb)
                          when 'derived_vm_allocated_disk_storage'
-                           resource.allocated_disk_storage
+                           resource.allocated_disk_storage.try(:to_f)
                          end
       @value[metric]
     end