September 2026 Supply Chain Activity Index: 43.7, and Trailer Demand Moved First

    September 28, 2026•7 Minutes

    Last month’s Index, covering July, fell to 36.4 and wiped out the spring rebound. This month it came back hard.

    The September 2026 WOW Supply Chain Activity Index, which reports August data, came in at 43.7, up 7.2 points from July. That’s the Index’s highest level since February 2023, its biggest one-month gain of the year, and 10.3 points above the January 2026 low of 33.4. It’s still inside the Contraction zone. But where the gain came from tells you more than the number itself.

    Trailer demand turned before the public data did

    Most of August’s gain came from WOW’s own yards. Our Deployment Ratio went from 0.75 to 1.18 as dry van on-rents outpaced dry van off-rents for the first time since March. That one series contributed 6.0 of the 7.2 points. The eight public data series added about 1.2 points combined.

    The Deployment Ratio compares trailers going out on rent to trailers coming back. Below 1.0, more trailers are being returned than rented. Above 1.0, more are going out than coming in. August’s move from 0.75 to 1.18 means the ratio flipped from net returns to net rentals in a single month.

    Here’s why that matters. When companies aren’t sure demand will hold, they don’t sign a warehouse lease. They add capacity they can give back. Short-term trailer storage is that capacity, so it shows up in rental data well before it shows up in leasing or utilization numbers.

    “Our trailer data showed positive movement before the macro data did. Dry van on-rents beat dry van off-rents in August for the first time since March, and that shows up in our yards a month before it reaches the other data points. This means the market is willing to add capacity again, but only capacity it can hand back, which is where every recovery starts. It’s important to note that one month doesn’t make a turn, so we’re watching September.” — John Brooks, CEO, Warehouse on Wheels

    The macro picture is mixed

    The public series didn’t move together in August:

    That last one is the gap to watch. Warehouses reported themselves less full in August while trailer deployment climbed. If September’s data closes that gap, the turn is real.

    What 43.7 on the Supply Chain Activity Index means

    The Index runs 0 to 100, with 50 as long-run neutral. Readings between 30 and 45 fall in the Contraction zone, and 43.7 sits at the top of that band. The Index hasn’t reported above 45 since early 2023. (New to the Index? Here’s how the monthly composite is built.)

    So read August as the top of Contraction, not the start of expansion. Across the first eight months of 2026, the Index is averaging 39.6. One month above that average isn’t a trend.

    What this means for shippers heading into Q4

    A reading at the top of Contraction is an in-between market. Demand is showing signs of life, but nothing in the data says yet that it will hold. For anyone planning peak-season space, that points to a few practical moves:

    • Keep commitments short. The companies driving August’s gain added capacity they can hand back. Do the same: plan for extra space through peak, but avoid terms that run long past it.
    • Shop your options before you sign. LMI Warehousing Utilization fell to 59.6, so warehouses reported more open space in August. That can mean better lease terms, but a lease still ties you to space you may not need in February.
    • Line up the plan now, pull the trigger later. Know where extra capacity would go (dock doors, yard room) and who would supply it. If next month’s reading confirms the turn, you can move fast instead of scrambling for space in November.

    What to watch in the October Index

    One strong month doesn’t make a trend. The October 2026 Index, which will report the September reading, will show whether August was the start of a turn or a one-time jump.

    • If the September reading comes in at 43 or higher, that’s two strong months in a row, a sign the market is turning and companies are adding space ahead of peak season.
    • If the September reading slides back into the high 30s, August was likely a one-month spike, and the market is still where it’s been most of 2026.

    Either way, Q4 is close. If you’re a 3PL, retailer or distributor still sorting out holiday space, our Q4 demand and seasonal inventory guide and the 3PL Playbook walk through how to add space without locking in a lease.

    Add capacity you can hand back

    The market is telling us the same thing our customers are: flexible capacity first, commitments later. WOW’s dock-height storage trailers drop at your door from 37 locations across the U.S., Canada and Mexico, and go back when the rush is over. Get a quote and we’ll help you size it.

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