The committee published its evidence. Here is what changed between drafts.

This is fictional sample content, created to demonstrate the layout. The places, people and figures in it are invented. It is not reporting.

Select committees publish written evidence as received. Occasionally a witness files a revised version, and both stay on the record.

That happened here, and the comparison is instructive. The first draft gives a cost range. The second gives a single number at the bottom of that range, and removes the sentence explaining what the top of the range assumed.

The third change is a footnote. In the first version it cites an internal model. In the second it cites a published paper that does not contain the figure.

We put all three to the organisation. It said the revision corrected an error and that the published paper was cited "for context". It did not say what the error was.

The committee has asked for a further note by the end of the month.