CN's 12% Grain Gain and 20% Auto Gain Require Commodity-Specific Rail Plans
CN's third-quarter traffic grew, but the headline conceals two very different capacity stories. Revenue ton-miles increased 4% overall, while grain and fertilizer traffic rose 12% and automotive traffic jumped 20%. At the same time, coal, forest products, and intermodal declined.
That is not one network trend. It is several commodity cycles competing for locomotives, crews, cars, terminals, and interchange windows on the same railroad. A shipper that plans from the 4% system average risks being short of the assets that matter on a fast-growing lane while reserving capacity where traffic is weakening.
The practical response is a commodity-lane capacity plan: a dashboard and operating cadence that models each flow by equipment, origin, destination, terminal path, and service requirement.
Averages hide the operational demand
FreightWaves reported that CN's revenue ton-miles rose 4% in the third quarter, including gains of 12% for grain and fertilizer and 20% for automotive. Those increases helped offset declines in coal, forest products, and intermodal traffic. CN continued to forecast low-single-digit revenue-ton-mile growth for 2026.
The mix matters more than the total because commodities do not consume interchangeable capacity. Grain needs covered hoppers, country elevators, export terminals, and seasonal unit-train slots. Finished vehicles move in autoracks through assembly plants and vehicle distribution centers. Forest products require different cars, loading practices, and destinations. Intermodal depends on terminals, cranes, chassis, containers, and scheduled train blocks.
Even when two commodities produce the same number of revenue ton-miles, they may create completely different pressure at a yard or interchange. Distance, train length, empty-car repositioning, terminal dwell, loading variability, and customer switching requirements change the true capacity burden.
Model five constraints separately
Start with a lane-by-commodity forecast in weekly units, then translate that demand into five resource plans.
Cars. Record the required car type, cars per shipment or train, loaded cycle time, empty return time, maintenance allowance, and usable fleet. A grain hopper completing a 12-day round trip cannot support the same weekly volume as one returning in nine days. Track median and 90th-percentile cycle time so a good average does not hide peak shortages.
Terminals. Map every origin elevator, assembly ramp, classification yard, port terminal, and interchange. Set practical throughput by shift and identify the shared facilities where growing commodities collide. Terminal capacity should reflect receiving hours, track space, loading or unloading rate, and the cutoff for the next scheduled train.
Crews and locomotives. Translate train starts into qualified crew and power requirements by territory. Growing automotive volume may need frequent scheduled service, while grain often moves in large unit trains. Both can increase demand even when weaker commodities release cars elsewhere, because people and locomotives cannot instantly move to the right subdivision.
Dwell. Separate origin dwell, yard dwell, interchange dwell, destination dwell, and empty-release delay. Each delay has a different owner. A two-hour improvement at a congested terminal may create more usable capacity than leasing additional cars that will simply join the queue.
Interchange. Measure planned versus actual handoff time, missed connections, receiving-road acceptance, and data completeness. Capacity promised by the originating railroad is not usable if the next carrier or terminal cannot accept the traffic on time.
Use operating metrics as early warnings
Network fluidity determines whether nominal capacity becomes actual service. In a July report on CN's volume growth, FreightWaves noted that car velocity, train speed, and dwell in the railroad's Western Region improved roughly 3%. Those measures should sit beside volume forecasts because a small change in cycle time compounds across a large fleet.
For context, FreightWaves reported that CN's fourth-quarter 2025 revenue ton-miles reached 61.7 billion, up 4%, while through dwell fell 1% to seven hours and car velocity improved 2% to 215 car-miles per day. Those improvements show why a capacity plan must include both demand and asset productivity. More volume does not always require assets in direct proportion if cars move faster; slower cycles can erase apparent spare capacity just as quickly.
Set alerts around the operating chain rather than waiting for missed deliveries. Useful signals include car orders exceeding confirmed supply, empty cars arriving late, origin loading queues, terminal dwell above the lane baseline, missed interchange connections, train-plan substitutions, and destination unload delays. Show each alert by commodity and lane so a strong grain corridor does not mask deterioration in automotive service—or vice versa.
Build a commodity-lane dashboard
The dashboard should answer four questions for every commodity and origin-destination pair:
- What demand is forecast, committed, tendered, and actually moved?
- Which cars, terminals, crews, locomotives, and interchanges constrain the next four to 12 weeks?
- How much capacity is confirmed, probable, or unprotected?
- What is the service and financial consequence if the plan fails?
Use weekly buckets for near-term execution and monthly buckets for seasonal allocation. Include forecast confidence, customer priority, inventory cover, production or harvest milestones, demurrage exposure, and truck or alternate-rail options. A single red-yellow-green status is not enough; users need the constraint, its owner, and the next decision date.
For grain, that may mean reserving hopper supply and export-terminal slots before harvest peaks. For automotive, it may mean protecting autoracks and assembly-plant switching windows as production schedules rise. For declining segments, it may mean releasing tentative capacity while retaining a reactivation trigger if orders recover.
Turn mixed demand into explicit allocation rules
Define allocation rules before shortages emerge. Protect loads tied to production continuity, export cutoffs, contractual delivery windows, or limited inventory first. Then use confirmed orders and forecast accuracy to allocate remaining capacity. Do not allow the fastest-growing commodity to absorb every flexible asset without measuring the cost imposed on other customers and lanes.
Review the plan jointly with carriers, terminals, and internal sales and operations teams. The railroad sees network constraints; the shipper sees production, inventory, and customer priorities. Connecting those views creates a plan that can survive mixed freight cycles.
CN's 4% total growth is useful context, but the 12% grain and fertilizer gain and 20% automotive gain are the actionable signals. Commodity-specific planning turns those signals into equipment decisions, terminal reservations, service protections, and timely alternatives.
Ready to manage rail capacity, commodity forecasts, milestones, and exceptions in one operating view? Request a CXTMS demo and build a capacity plan around the freight that is actually moving.
