
A standardized economic asset representing train-miles, car-miles, ton-miles, slots of measurable rail infrastructure capability under defined operating conditions.
train-miles, car-miles, ton-miles, slots define the canonical capacity units.
Ton-miles, passenger service, train paths, reserved slots, velocity, dwell, and availability establish the operational record.
Scarcity, utility, durability, demand, transferability, and revenue potential determine institutional relevance.