Method and evidence grades

Every figure in this section carries a letter after it. That letter is not a disclaimer - it tells you how far the figure can be used. Grade A can go straight into a contract. Grade B can support a judgement. Grade C can only set a direction. Using a C-grade number to sign against is the one misuse we would ask you to avoid.

The three grades

Grade	Definition	Use it for	Do not use it for
A Official primary	Government gazettes, regulator filings, standards-body catalogues, listed-company annual reports - anything retrievable by document number	Contract terms, acceptance criteria, compliance files	- (but always confirm you hold the latest version)
B Authoritative secondary	Published research from consultancies, investment banks or industry bodies, traced to publisher and publication date; or vendor-published product and financial figures	Forming a judgement, setting direction, justifying a decision internally	Acceptance criteria (the underlying method and sample are usually not visible)
C Our own derivation	Our arithmetic, synthesis or judgement on top of A and B material; or second-hand figures we could not cross-verify	Setting direction, working out what to ask	Citing as fact, writing into contracts, using as acceptance criteria

Three rules we hold ourselves to

We do not reconcile conflicts - we publish them. When sources disagree on the same metric we neither average them nor pick one. We publish the spread together with the likely reason for it. The tenfold gap on the semiconductor page and the contradictory share figures on the harmonic drive page are both this rule in action. A smoothed-over number is far more dangerous than an honest range.
For anything perishable we give the method, not the number. Lead times, prices, shares and control status all move. So we prioritise where to look and which number to look up over copying a value that expires. Every Last verified line on these pages means exactly that.
If we did not verify it, we say we did not verify it. Where we could not reach the primary text, the source list says so explicitly. That is not modesty - it is telling you which step you still need to take.

On compliance information

Where these pages touch export controls, we publish only facts and proposal status that you can check yourself by docket number, and we separate "proposed" from "in force" explicitly. We offer no workaround, and we make no assertion about whether any specific company appears on a restricted list - an assertion of that kind, unverified against the primary source, is paid for by the reader. That is not acceptable to us.

Four steps to verify any figure yourself

Read the grade before the number. A C-grade figure is a direction however precise it looks. Decide first whether it is worth your time to check.
Follow the source list to the document number. Every page's sources section gives the file number, docket number or publisher. If it cannot be retrieved by number, it cannot be checked.
Confirm the date. Check Last verified at the top of the page and the update line at the bottom. Control status, lead times and market shares need rechecking beyond a quarter.
Ask the supplier for the measured value for your own specification. An industry range never substitutes for a measured report on the specific model - this is the one step on this page you should not skip.

Review cadence

Data type	Review frequency
Export control status, tariffs, standard numbers	Before every shipment; at least quarterly
Lead times, prices, capacity	Quarterly
Market share and localisation rates	Every six months
Cost structure and BOM shares	When the underlying study is updated

Last updated 2026-10-09.