According to the billing ton-km, it refers to the sum of the product of the tonnage of each batch of goods and the transportation distance completed by the railway transportation department during the reporting period, that is, the number of tons of goods completed in the railway freight transportation work. The calculation formula is:

Freight turnover of the whole railway (ton km)

= σ [Weight of each batch of goods (ton) × corresponding transportation distance (km)]

Freight turnover of railway administration (ton-km)

= σ [Weight of each batch of goods within the scope of this bureau (ton) × corresponding transportation distance (km)]

The transportation distance of goods refers to the charging mileage between the departure and arrival of goods, which is generally calculated according to the shortest route except for special designated routes. The turnover of railway goods is calculated according to the invoice and the delivery time of the goods, which is generally calculated by the statistical factory on a monthly, quarterly and annual basis.

Railway freight turnover is the main index to assess the railway freight workload, and it is also the index to calculate the internal transportation cost, labor productivity, average freight distance and average freight density, and it is the basis for the distribution of transportation income among railway bureaus.