American diesel is a penny above where it was, and the argument is about whose penny it is

A Financial Times analysis of federal data puts the average since January 2025 at $4.09 a gallon against $4.08 across the previous four years.

The lead item in Heatmap's morning briefing is a Financial Times analysis of Energy Information Administration data finding that US diesel has averaged $4.09 a gallon since January 2025, against $4.08 across the preceding four years. The piece attributes recent pressure to inflation from the Iran war, and notes the Treasury secretary discussing possible negotiations to reopen the Strait of Hormuz to commercial shipping.

The gap being reported is one cent, which is a way of saying that the price of diesel has not meaningfully moved across two administrations. That is worth a card mainly as a corrective. Diesel is the fuel under freight, agriculture and construction — it is an input cost to most of the physical needs this project tracks, and it is the clearest example of an energy source with no learning curve underneath it. Solar modules fell roughly 99.6% over five decades because manufacturing them gets cheaper with scale. Extracted fuels do not work that way, and five years of flat nominal pricing during a period of general inflation is what a non-learning commodity looks like on a good run.

Two limits on this item. It is a newsletter briefing carrying five stories, not a reported piece, so the detail sits with the FT. And a one-cent difference framed as a political result is a framing choice rather than a physical finding — nominal prices holding flat through an inflationary stretch is arguably the opposite of the headline's implication.

Source: Heatmap