Platton Import Index methodology
This methodology sets out how the monthly Platton Import Index is built: the three public data groups behind it, ocean spot rates, US import volumes and rule changes, and the lanes each number is read on. Every figure cites a named public source, and what Platton adds is the selection, the lane focus and the importer's reading. It is not a proprietary rate calculation and not a forecast.
What the Index tracks
Three blocks, every month. Rates: ocean spot movements on the import lanes listed below, Asia and Europe into the US, per Drewry's publicly published World Container Index and the publicly published Freightos Baltic Index lane series. Volumes: national containerized imports per Descartes' monthly Global Shipping Report, and gateway volumes from the port authorities' own published statistics, primarily Los Angeles, Long Beach, New York and New Jersey, and Savannah. Rules: tariff and customs changes as published by USTR and CBP, restricted to items that change what an importer pays or files.
The lanes we follow
The rates block covers three origin groups, in the order they carry client volume. Transpacific first: China to the US West Coast and China to the US East Coast hold the largest share and set the tone for the whole market, so they anchor every issue. Europe next: North Europe to the US East Coast, read on the publicly published Freightos Baltic Index series for that lane, because European origins price on their own cycle and can move in the opposite direction to Asia in the same week. Then the wider Asia set: Vietnam to the US and India to the US, the fastest-growing origin alternatives among the companies Platton serves, with other Southeast Asian origins added as public lane data allows.
Lanes are reviewed as client volume shifts, and a lane change is announced in the issue that applies it. Where a lane has no public weekly rate series, the Index says so in that issue rather than filling the gap with an estimate.
Cadence and revisions
The Index is compiled monthly by Platton's operations team and publishes on the 20th of each month, or the first working day after when the 20th falls on a weekend. That date follows the data: national and gateway volume figures for the previous month are published by the middle of the month, and the rate reading is taken within days of publication. The main page is updated in place so one URL always carries the current issue, and past issues are archived by month. If a source restates a figure, the correction appears in the next issue and is marked as a correction, not silently replaced.
What the Index is not
It is not a rate quote, not a prediction, and not a replacement for the detailed guides: surcharge mechanics live in the ocean freight rates guide, transit realities in the transit times guide, and a bookable price for a specific shipment comes from a quote, not from an index.