What the freight PPI measures, and why it is not dollars a mile

The dry van truckload index read 195.6 in July on the Bureau of Labor Statistics producer price index, down 1.3% on the month and up 8.1% on the year. That 195.6 is not a rate. It is not $1.96 a mile, and it does not convert into one. It is an index, and reading it as a price is the fastest way to get a freight number wrong.

An index measures change from a fixed starting point. This one is set so that December 2003 equals 100, so a reading of 195.6 says prices in this category are about 96% above where they sat in that base month. The useful information is in the movement: 1.3% lower than June, 8.1% higher than a year ago. The level on its own, 195.6, means nothing in dollars and cannot be turned into cents per mile.

It also lags what you feel. The index blends contract freight with spot freight. Most of what moves a driver's week is the spot market, but the PPI mixes spot business with longer contract rates that reset quarterly or once a year, so it turns later and more gently than the spot market does. A soft stretch on the load boards can take months to show up here, or barely register at all.

July's figure is preliminary and will be revised. One month read in isolation can move on the next release; the direction across several months is the part worth trusting.

And it is a whole category, not your truck. The dry van series is NAICS 484121, an aggregate of thousands of long-haul truckload carriers. Your lane, your shipper and your fuel surcharge can go the other way in the same month the index falls.

The broader all-trucking index, 205.4 in July and down 1.9% on the month, is a weighted blend of every segment beneath it. That makes it a clean headline and a poor basis for a decision: it can hide two segments moving in opposite directions inside a single number.

So what is it good for? The shape of the market over time. If you want a figure you can put into a rate conversation, use the series that are already in real units. The site carries diesel in dollars per gallon and refrigerated produce in dollars per mile; those are actual prices you can act on. The PPI is the long trend line, not the number you quote on a load.