Corrections policy

A correction to a data table moves the vintage label on the affected table forward, so the version a reader is looking at is always identifiable. The table itself carries the source and the period it covers, and the vintage range is the record of when it was last republished. A reader who needs to know whether a figure has changed can compare the vintage on the page with the one they captured earlier.

A correction to prose is handled according to how material it is. A wrong percentage, a misattributed date or a claim that overstated the evidence is corrected in the text and described where the error was material to the argument, so a reader who quoted the old wording can see what changed. A typo, a broken link or a formatting slip is fixed quietly, because a correction notice for a misspelling would bury the notices that matter.

Where a correction changes the conclusion a page draws, the page says so explicitly rather than editing the conclusion into place. The reasoning that led to the original conclusion is left visible, with a note on what the corrected figure shows instead. A reader should be able to see not only what the site now says, but what it said before and why it changed.

Every dataset on the site carries a vintage: the period it covers and the point at which it was last republished. A material update — a revised source, a corrected figure, an added year — moves that vintage forward and is dated. The date is the date of the update, not the date of the original publication, so a reader can tell at a glance how current the material is.

The live series are the exception, and the site is explicit about it. The BTC/USD spot price and the daily candles are fetched from the Coinbase Exchange public API, cached for a few minutes and re-fetched on demand. They are readings rather than settled records, they change between visits, and each one carries the timestamp of the moment it was fetched. They are not revised, because they are not stored as history: each fetch replaces the cached value and the previous reading is gone. If you need a permanent record of a particular day's price, take it from the curated daily candles rather than the spot panel, and note the date you captured it.

The data sources and methodology page sets out the vintage of every dataset in full, along with the periods where the compiled record is genuinely uncertain.

The site does not quietly rewrite published analysis. Once a page has drawn a conclusion from the record, a later change to that conclusion is made visibly: the page states that it has been revised, what the earlier version said, and what the corrected material shows. The earlier reasoning is not deleted, because a reader who followed it deserves to see where it led and why it no longer holds.

This applies to the site's own analysis as much as to a reader's report. When the publisher revisits a page and finds that a conclusion no longer follows from the data — because a source was revised, because a longer window is now available, or because the original reasoning was simply wrong — the revision is described on the page rather than applied in place. The record of what the site said before is part of the record.

The editorial standards page sets out the sourcing and review standards behind this policy, and the disclaimer states the educational purpose of the site and the limits of what it offers.