Market Data

What the PPI for Aluminum Mill Shapes Measures, and the 3 Inputs That Move It

A plain-English guide to the BLS index factory buyers watch for aluminum sheet, plate, bar, and extrusions, how it is built and what actually pushes it up or down.

The Bureau of Labor Statistics' Producer Price Index for Aluminum Mill Shapes tracks the average selling price U.S. mills receive for sheet, plate, bar, and extruded shapes. As of May 2026 it stood at 404.86 (1982=100), meaning those prices are roughly 4.0 times their 1982 level, up about 36.8% from a year ago. For procurement leads and estimators who see the index cited in surcharge letters and escalation clauses, knowing what sits inside the number is the difference between reading the market and being read to.

What the index actually covers

The index measures the first-sale price mills charge, net of discounts and surcharges, for semi-fabricated aluminum: rolled sheet and plate, drawn bar and rod, and extruded shapes. It is not the London Metal Exchange ingot quote, and it is not what a service center or distributor charges after its own margin, it sits between the two, which is exactly why contracts reference it. The 1982=100 base means every reading is a ratio: at 404.86, mill-shape prices average about 4.0x what they were in the base year. BLS publishes the figure monthly, with a short lag and occasional revisions, so the May 2026 reading is the freshest complete observation.

The three inputs that move it

First, metal cost: the LME aluminum price plus the U.S. Midwest delivered premium typically makes up half or more of a mill product's price, so moves in the global ingot market and in tariff-sensitive premiums flow through within a billing cycle or two. Second, energy: smelting and remelt are among the most electricity-intensive processes in manufacturing, and casthouse and rolling operations burn significant natural gas, so sustained power and gas moves show up in conversion pricing. Third, conversion cost itself, mill labor, capacity utilization, and freight. When order books are full, mills widen conversion spreads; when they are hunting for volume, spreads compress even if metal is flat. The index blends all three, which is why it can move when the LME does not.

In practice, decomposing a move takes two comparisons. If this index and the global aluminum price move together, the story is metal, and there is little a mill or a buyer can do about it beyond hedging. If the index moves while ingot is quiet, the action is in premiums or conversion spreads, which is negotiable territory, because it reflects domestic mill order books rather than the world market. That distinction decides how a procurement team responds to a surcharge letter: metal-driven increases get passed through or hedged; conversion-driven increases get benchmarked, challenged, and competitively bid. The BLS publishes the reading monthly, about two weeks after the reference month, and revises recent months as late survey responses arrive, so treat the newest print as firm direction rather than settled history.

PPI: Aluminum Mill Shapes, May 2026 (1982=100): 404.86. Ranged from 295.97 in May 2025 to 404.86 in May 2026 across the archived history.

What a reading like this means for a buyer

Translate the index into your own spend. A fabricator buying $1,500,000 of mill shapes a year is exposed to every percentage point the index moves: the current pace, up about 36.8% from a year ago, has added about $551,851 to that line over the past year. That is the practical use of the series, not predicting the LME, but benchmarking whether the price increase (or decrease) your mill or service center just passed along tracks the published market or exceeds it. If your supplier's move outruns the index by several points, the gap is negotiable; the index is the neutral referee both sides accept.

The index is not the LME quote and not the distributor's invoice, it sits between the two, which is exactly why contracts reference it.

Put your annual aluminum volume and a range of price moves into the metal price sensitivity calculator to see what each index point does to your material budget. Test your exposure

Published 2026-07-13.