diff --git a/src/depot.h b/src/depot.h
--- a/src/depot.h
+++ b/src/depot.h
@@ -51,7 +51,7 @@ void ShowDepotWindow(TileIndex tile, Veh
  */
 static inline Date GetServiceIntervalClamped(uint index)
 {
-	return (_patches.servint_ispercent) ? clamp(index, MIN_SERVINT_PERCENT, MAX_SERVINT_PERCENT) : clamp(index, MIN_SERVINT_DAYS, MAX_SERVINT_DAYS);
+	return (_patches.servint_ispercent) ? Clamp(index, MIN_SERVINT_PERCENT, MAX_SERVINT_PERCENT) : Clamp(index, MIN_SERVINT_DAYS, MAX_SERVINT_DAYS);
 }
 
 /**