Market Data

What the Truck Tonnage Index Actually Measures, and Why 117.70 Matters

A plain-English guide to the ATA's freight benchmark: how the index is built from carrier surveys, why 2015=100, and what a reading of 117.70 tells you about how much America is hauling.

The Truck Tonnage Index is the American Trucking Associations' monthly, seasonally adjusted measure of freight tonnage hauled by for-hire trucks, benchmarked to 2015=100, and its latest reading of 117.70 as of Apr 2026 means U.S. trucks are moving about 17.7% more tonnage than they did in the 2015 base year. The series, published through FRED and up about 3.4% from a year ago, matters because trucks carry roughly 72% of domestic freight tonnage: when this index moves, it is the physical goods economy moving.

How the ATA builds the number

Each month the ATA surveys its member carriers for the tonnage they actually hauled, aggregates the responses, seasonally adjusts them, freight has strong produce-season and holiday rhythms, and expresses the result as an index against the 2015 average, which is set to 100. An index, unlike a raw tonnage count, makes every month directly comparable: a reading of 117.70 says national for-hire truck freight is about 17.7% more tonnage than they did in the 2015 base year, in one number. Because the sample skews toward larger contract truckload carriers, the index reads the steady, contracted core of the freight market rather than the volatile spot fringe, which is precisely what makes it useful as a demand gauge rather than a rate gauge.

What it covers, and what it leaves out

The index measures for-hire carriage: freight moved by trucking companies for customers. It does not capture private fleets, the trucks retailers and manufacturers run themselves, nor rail, barge or air cargo, and tonnage is not revenue: a heavy load of steel coil and a light load of pillows count very differently by weight than by freight bill. Those exclusions matter for interpretation. A shift of freight between private fleets and for-hire carriers can move the index without any change in total goods movement, and a tonnage-weighted view naturally overweights the industrial economy, metals, building materials, food, relative to parcels. For a manufacturer, that industrial tilt is a feature: this index weighs the kind of freight factories ship.

A note on the monthly rhythm: the seasonal adjustment is doing heavy lifting. Raw truck freight surges ahead of holidays, sags in deep winter, and swells with produce season, so the unadjusted series swings in ways that say nothing about the economy. The ATA publishes both versions, and the adjusted one, the series charted here, is the one to quote. Even adjusted, single months get revised as carrier responses are completed, and one print can be moved by weather or a freight-embargo week. The professional habit is the same as with any survey-based indicator: read three months of direction before changing a plan, and treat the level as more trustworthy than the twitch.

ATA Truck Tonnage Index, Apr 2026 (2015=100): 117.70. Ranged from 112.10 in Oct 2025 to 117.70 in Apr 2026 across the archived history.

Trucks carry roughly 72% of U.S. freight tonnage. When this index moves, it is the physical goods economy moving.

Turning the index into your own units

The index converts to concrete volume with one division. A lane or network that moved 100,000 tons in the 2015 base year would, if it tracked the national index, be moving about 117,700 tons at today's reading of 117.70, the index value applied as a percentage. The same arithmetic works in reverse for capacity planning: dock schedules, trailer pools and carrier commitments sized to a 2015 baseline are now handling about 17.7% more tonnage than that baseline assumed. The reading is currently climbing, and up about 3.4% from a year ago, the two facts to carry into any conversation about freight budgets or dock throughput.

Use the freight cost per unit calculator to see what your current lanes and volumes actually add to each shipped unit. Run your freight economics

Published 2026-07-13.