02 · Definitions

Every glossary entry carries a label naming what kind of definition it is, because the four kinds carry very different authority and are otherwise indistinguishable on the page.

Statutory definitions are reproduced from the United States Code with the section cited. Language from adjacent statutory definitions is never merged into one, and where two related definitions sit near each other the entry separates them explicitly.

Regulatory definitions come from the Code of Federal Regulations, most often the Federal Acquisition Regulation. Where a regulation defines the same term differently in different parts, the entry says which parts and why they differ.

Agency definitions are the working constructs statistical agencies use to build a series. They are authoritative for that series and carry no legal force.

Economic term and industry usage mark conventions among analysts and practitioners, which have no single authority and vary in the field.

Institute framework marks a definition the Institute constructed because no adequate one existed. These are the entries a reader should scrutinise most closely, and labelling them is the point of the taxonomy.

Definitions that depend on a current federal determination carry a verification date. The critical minerals list is the case that established the requirement: it is revised at least every three years, uranium has moved on and off it twice, and an entry describing a superseded stage as current is wrong in a way that no amount of care at the time of writing prevents.

03 · Disagreement

Where two official sources give different figures for the same quantity, both appear. The entry does not choose one silently, and it does not average them.

The working test is whether the conclusion depends on the choice. Bureau of Labor Statistics publications give the 1979 manufacturing employment peak as both 19.6 million and 19.4 million; measured from either, the subsequent decline is about 35 percent, so the disagreement is a footnote and the entry says so. The Council on Environmental Quality has published both a 4.5 year average and a 2.4 year median for environmental impact statement completion; those support materially different arguments, so the disagreement is the finding rather than a footnote.

Where informed people disagree about interpretation rather than measurement, the entry states the strongest version of each position, including positions the Institute does not hold, and says what evidence would distinguish them.

04 · Marking analysis

Four annotation types appear throughout the library, and each means something specific.

Data presents a figure with its source, series identifier and period. Measurement note explains what a series does and does not capture, including seasonal adjustment, price adjustment, base year and scope. Contested sets out a live disagreement without resolving it. Institute analysis marks a conclusion the Institute has drawn rather than a finding it is reporting.

The last of these is the one that matters most. Where the Institute takes a position, the position is labelled as a position, and a reader who rejects it should still be able to use the surrounding evidence.

05 · Review and revision

Every entry carries a visible last-reviewed date. Review cadence follows how quickly the underlying material moves.

Definitions resting on a federal list or determination are reviewed at least every six months, and whenever the governing list is revised. Entries built on monthly or quarterly federal series are reviewed at least annually, and figures are refreshed when a revision changes them materially. Entries resting on statute are reviewed when the statute changes, which includes renumbering: the definition of the national technology and industrial base moved from 10 U.S.C. §2500 to §4801 effective January 2022, and most published references have not caught up.

06 · Corrections

The Institute corrects factual errors openly. A material correction is recorded at the foot of the affected entry with the date and a description of what changed and why, and the entry is not quietly edited.

A material correction is one that changes a figure, a source attribution, a statutory citation, or a conclusion. Copy edits, formatting and clarifications that leave the substance intact are not logged.

Corrections improve a reference work rather than damaging it, because a library that never records a correction is either not being checked or not admitting the results. To report an error, write to the Institute with the entry and the source you believe is correct.

07 · Series used in this library

Twelve sources supply every figure published in Learn. Each is described on the page where it appears, and the full register is available as a machine-readable file so that a reader, a newsroom or a retrieval system can check the whole set at once rather than page by page.

Download the register → CSV, or read it as JSON. Provenance records may be reused with attribution. The underlying data belong to the publishing agencies.

NoteThe two framework diagrams in this library are schematic. Bar heights show relative constraint and imply no quantities, so no dataset underlies them.

Corrections log

August 9, 2026 · When Did American Deindustrialization Begin?
The entry stated that the Bureau of Economic Analysis series measuring manufacturing value added as a share of GDP begins in 2005, and drew from that the conclusion that the output evidence cannot date the beginning of the decline. The 2005 start belongs to the quarterly series used in the chart. BEA publishes annual GDP-by-industry estimates for 1947 forward. The passage was rewritten to distinguish the series from the evidence base, and a measurement note on the classification break between historical vintages was added.

August 9, 2026 · What Is the U.S. Industrial Base? and Industrial base (glossary)
Both entries attached the phrase “capable of engaging in” to the statutory definition of the national technology and industrial base at 10 U.S.C. §4801(1). That language belongs to the definition of a technology and industrial base sector at §4801(4). Both entries now separate the two definitions and state the distinction.

August 9, 2026 · Critical mineral (glossary)
The entry described a 2025 executive order directing the U.S. Geological Survey to consider adding uranium to the critical minerals list, presenting a superseded procedural stage as current. Uranium was included in the final 2025 List of Critical Minerals published November 6, 2025. The entry was updated and now carries a verification date.

August 9, 2026 · Learn front page
The industrial system diagram and its caption described eight inputs while the synthesis entry described nine. The framework is now fixed at nine inputs across the library and named the Industrial Capacity Framework. The caption was also revised to state that capacity is limited by one or more binding constraints and that relieving one commonly exposes the next.