Line of Travel derives a Line of Travel (LOT) code, which is comprised of a 4-digit Line of Travel sequence number and a 1-character Line of Travel sequence code. The Line of Travel sequence code is either "A" for ascending, or "D" for descending. Line of Travel then appends the LOT code to all name and address records with a Delivery Point Barcode and a Carrier Route that matches the Line of Travel Master File.