diff --git a/Netdisco/lib/App/Netdisco/Core/Macsuck.pm b/Netdisco/lib/App/Netdisco/Core/Macsuck.pm
index 7426ce9e..100e9b9f 100644
--- a/Netdisco/lib/App/Netdisco/Core/Macsuck.pm
+++ b/Netdisco/lib/App/Netdisco/Core/Macsuck.pm
@@ -124,7 +124,7 @@ sub do_macsuck {
     time_last => { '<' => \$now },
   })->update({ active => \'false' });
 
-  debug sprintf ' [%s] macsuck - removed %s fwd table entries to archive',
+  debug sprintf ' [%s] macsuck - removed %d fwd table entries to archive',
     $ip, $archived;
 
   $device->update({last_macsuck => \$now});