How to structure this clause
- Identify the actual trade lane. Fix the specific origin-destination pair the contract moves goods on. Neither benchmark is a single global number that fits every shipment.
- Pick the matching index. Use the Drewry World Container Index at route level, which both sides can verify without a subscription, or a Freightos Baltic Index lane code such as FBX01. Match it to the lane, not a global composite.
- State the access basis for FBX. If the clause cites the Freightos Baltic Index, name the lane code and state whether the parties hold a Freightos Terminal subscription or are relying on the free weekly commentary.
- Keep surcharges on separate lines. Benchmark the fuel surcharge (BAF), peak-season and GRI surcharges, and container and equipment fees separately. Folding them into the base-rate escalation hides that they move on different schedules.
- Do not use a global average for one lane. A rate spike on one trade lane does not mean another moved with it. Citing a global composite for a single-route contract produces an adjustment unrelated to what that route costs.
Two real indices, different access
Container freight has two named, widely used benchmarks: the Drewry World Container Index (WCI) and the Freightos Baltic Index (FBX). Both are real, both are referenced across the shipping industry, and both differ in how much data is actually free to check.
Drewry World Container Index
The WCI is a composite of spot rates across eight major East-West trade routes, published weekly in US dollars per 40-foot container. Drewry publishes the current composite reading and route-level detail as a free tracker at drewry.co.uk. This is one of the few freight benchmarks a contract can cite and both sides can verify without a subscription.
Freightos Baltic Index
The FBX covers twelve global trade lanes, each with its own code, for example FBX01 (Asia to North America West Coast) or FBX11 (Asia to North Europe), priced in US dollars per 40-foot equivalent unit. Headline moves on individual lanes appear in Freightos' free weekly market commentary. Full live, lane-by-lane data requires a Freightos Terminal subscription. If a contract cites the FBX, name the specific lane code and state plainly whether the parties have terminal access or are relying on the free weekly commentary.
A free BLS cross-check
BLS publishes a US price index for deep sea freight transportation, series PCU483111483111. It is free and updated monthly. It is a producer price index for the service, not a container spot rate for a lane, so it cannot replace the WCI or FBX in a lane-based clause. It can serve as a sanity check, or as the index where neither party wants a subscription and the contract is not tied to one lane. The chart below shows how it compares with oil prices.
Sources: PCU483111483111 (Deep Sea Freight Transportation); EIA via FRED, MCOILWTICO.
Since 2017, this index has followed the WTI crude price about 3 months later and moved about a third as far as it over a year.
Over the 12 months to Sep 2026, the WTI crude price rose 52.1% and this index rose 36.8%.
Match the index to the actual lane
Neither index is a single global number that fits every shipment. A contract moving goods from Shanghai to Los Angeles should reference that specific lane's rate, not a global composite that blends routes the shipment never uses. Using the wrong lane, or a composite when a specific lane exists, drifts from what the shipment actually costs to move.
Build the composite around what actually drives ocean freight cost
| Component | Benchmark | Note |
|---|---|---|
| Base freight rate | Drewry WCI (route-level) or FBX (lane code) | Match to the actual origin-destination pair |
| Fuel surcharge (BAF) | Carrier-published bunker adjustment factor | Usually quoted separately from the base rate, confirm it is not double-counted |
| Peak season and GRI surcharges | Carrier tariff filings | Seasonal, not a steady index, budget for volatility separately from the base rate |
| Container and equipment fees | Carrier or terminal tariff | Regional, varies by port |
A worked example
Container spot rates are not stored on this site, so this example uses the BLS deep sea freight series. The arithmetic is the same for a WCI route reading or an FBX lane code. Fuel surcharges, peak season fees and equipment fees move separately and belong on their own lines, not in the base rate escalation.
Take a contract signed in September 2025 with $400,000 of ocean freight scope, invoiced in September 2026.
| Base index, Sep 2025 | 390.95 |
| Current index, Sep 2026 (revisable) | 534.796 |
| Ratio, 534.796 ÷ 390.95 | 1.3679 |
| Amount at signing | $400,000 |
| Adjustment added to that amount | +$147,176 |
Live figures from the stored series, updated when the provider publishes. Sep 2026 can still be revised, so a clause should say whether the invoice uses the first published value or is trued up later.
Don't cite a global average for a specific lane
Container freight rates vary enormously by lane. A Transpacific rate spike does not mean an Intra-Asia lane moved the same amount. Citing a global composite, whether Drewry's or Freightos', for a contract on one specific route produces an adjustment that has nothing to do with what that route actually costs.
BLS publishes several ocean freight series, and they do not move together. Name the exact series code, with the BLS title next to it.
Over the 12 months to Sep 2026, these series moved differently. On the same $400,000, the gap between the highest and lowest is $120,183.
| Series | What it covers | 12 months | On $400,000 |
|---|---|---|---|
PCU483111483111 | Deep Sea Freight Transportation | +36.8% | +$147,176 |
PCU4831114831115 | Deep Sea Freight Transportation, Freight Transportation Services | +36.8% | +$147,176 |
PCU483113483113 | Coastal and Great Lakes Freight Transport | +6.7% | +$26,994 |