What is tpm and mpm meaning in iata rules?

In IATA rules, TPM stands for "Total Per Mile," while MPM refers to "Maximum Permissible Mileage." TPM is a unit of measurement used to assess the total distance traveled for air cargo shipments, while MPM sets the upper limit on the distance that can be billed for certain air cargo rates. These terms help standardize pricing and ensure that shipping costs are calculated fairly based on distance.