The Bureau of Transportation Statistics reported an average diesel price of $4.96 per gallon for July, down 1.4% from June but 31.1% above July 2025. The Energy Information Administration’s separate weekly series measured $5.348 for the week of August 3.
Those figures describe different windows. A monthly average smooths every week in July, while a weekly reading responds more quickly to the market carriers are buying in now. Using one as though it were the other can distort a surcharge review or lane estimate.
Customer contracts should identify the index, geography, publication schedule, base value, adjustment frequency, and lag. If the agreement says monthly and the fleet models weekly, the internal margin view and customer invoice will move at different speeds.
That lag should be visible by account. A carrier can be operationally profitable over the term of a contract while experiencing a painful cash period when fuel rises quickly and recovery arrives later.
Dispatch should use a current planning value for the route, not blindly copy the billing index. Finance should then reconcile the actual fuel cost, the contractual recovery, and the timing difference instead of treating surcharge revenue as a complete offset.
The useful question is not which public number is correct. It is which number belongs to the decision being made: today’s dispatch plan, this week’s purchase strategy, the customer’s invoice, or a longer historical comparison.