Reference
Glossary
The terms the brief uses, defined the way the freight side says them.
- The DOE number
- EIA's weekly average retail price of on-highway diesel, released Mondays. The trade calls it the DOE number because EIA sits inside the Department of Energy. It is the contractual index of US trucking: most fuel surcharge schedules between carriers, brokers and shippers peg to this exact figure. When your surcharge changes on Tuesday, this number is why.
- Fuel surcharge
- The line item that passes fuel price risk from the carrier to the shipper. A typical schedule sets a base fuel price (the peg) and adds a fixed amount per mile for every increment the DOE number sits above it. The schedule is a matter of contract; the index it reads is public and it is the number on our front page.
- On-highway diesel
- Taxed pump diesel, the fuel trucks buy at retail. Distinct from dyed off-road diesel (farm and construction fuel, untaxed, illegal in a road tractor) and from wholesale prices. Every retail figure on this site is on-highway.
- ULSD (Ultra-low sulfur diesel)
- Diesel with 15 parts per million of sulfur or less. Since 2006 it is effectively all on-highway diesel sold in the US, so "diesel" and "ULSD" name the same fuel at the pump. Our spot series are ULSD specifically.
- PADD (Petroleum Administration for Defense District)
- The five regions EIA reports petroleum data by. PADD 1 is the East Coast (split into 1A New England, 1B Central Atlantic, 1C Lower Atlantic), PADD 2 the Midwest, PADD 3 the Gulf Coast, PADD 4 the Rockies and PADD 5 the West Coast. The diesel survey also breaks out California, and PADD 5 with California removed.
- Spot price
- The price of a bulk cargo of fuel changing hands at a trading hub, quoted daily on business days. We carry EIA's two ULSD spot series, New York Harbor and the Gulf Coast. Spot is untaxed wholesale; it is the layer pump prices follow, usually with a lag of days to weeks.
- Rack price
- The wholesale price at a terminal loading rack, where tanker trucks fill up for delivery to stations and fleets. Rack sits between spot and retail. EIA does not publish daily rack prices, so this site does not carry them; do not read our spot series as your rack quote.
- Retail-minus-spot margin proxy
- Our derived gap between the pump price and the nearest-business-day ULSD spot. It proxies the whole retail layer: taxes, distribution, station margin, all of it. It is not a station's actual margin, because retail includes roughly 60 to 80 cents of federal and state fuel taxes that spot does not. Wide and widening means the pump has not followed the wholesale market down, whatever the reason.
- Cents per mile
- Fuel cost expressed the way operators plan: price per gallon divided by miles per gallon. Our figures use a stated reference of 6.5 mpg, a plain mid-fleet figure for a loaded Class 8 truck. Your truck's number differs with spec, load and terrain; the reference is for comparing weeks, not billing.
- Deadhead / loaded mile
- A loaded mile is driven with freight; a deadhead mile is driven empty to reach the next load. Fuel burns on both, revenue rides on one, which is why per-mile fuel math understates the true cost of a run with a long empty leg.
- Owner-operator
- A driver who owns the truck and buys the fuel. The DOE number hits an owner-operator twice: at the pump, and in the surcharge that may or may not make it back through the party holding the freight contract.
- Winter blend
- Cold-weather diesel, cut with kerosene or treated so the fuel does not gel. It costs more to make and slightly reduces fuel economy, one reason northern diesel premiums widen in winter. The switch runs roughly October through March, by region.
- CARB diesel
- California's own diesel specification, tighter than the federal one and made by fewer refineries. Part of why California pump prices sit far above the rest of the country, alongside the state's taxes and fees.
- Versus the 5-year median (vs-5yr-median)
- A series compared against the median value for the same calendar week over the prior five years. Our standard "is this normal" yardstick. Median, not average, so one freak year cannot drag the baseline. We label it honestly everywhere.