Correspondence
The letters
There are three, they are separate, and you choose each one. Nothing is bundled, and choosing one does not sign you up for the others.
The annual letter
Once a year. It restates the method and says what changed in it during the year — a conversion factor, a rounding rule, a note added. If nothing changed, the letter says that and is shorter.
Price-change notices
When a reference price in the preset table is revised, a short notice with the old figure and the new one, and the date the change took effect. These arrive when the services change their prices, which is not often and is not on a schedule.
Notes to the Método
When a note is added or corrected on the Método page, the note itself, in full. You are not asked to visit the site to read it.
What we do not send
No offers, no discounts, no products, no partner mail, no third-party advertising, no digests of anything. Nothing is sold in these letters, because there is nothing to sell. Your ledger stays in your own browser, and we never see it.
How your address gets on the list
You enter it on the ledger page and tick the letters you want. Then we send one message to that address with a link, and the address joins the list only when you open that link. Until then it is a pending record and receives nothing else.
IF IT IS NOT OPENED AT ALL, THE ADDRESS IS DELETED AFTER SEVEN DAYS
AND NOTHING IS EVER SENT TO IT.
We have never bought, rented, imported or scraped an address list, and we never will. An address is here because its owner typed it here.
What we record when you subscribe
The date and time in UTC, the internet address the request came from, the page the form was on, the version of the consent text you agreed to, and which letters you chose. That record exists so the question «did this person actually ask» has an answer. It is shown to you in the confirmation message, so you see exactly what we hold.
How you leave
Every letter carries a link that removes you in one click — no password, no login, no questions, no offer to reconsider. Letters also carry the standard unsubscribe headers, so your mail programme can show its own button and that works too.
Leaving deletes the record. We do not keep a list of people who left, other than the suppression list that stops mail being sent again to an address that bounced or complained.
If a link ever fails, write to letters@cadihn.org and it is done the same day.
Consent text version corr-v1-2026-08.