Cookies and browser storage

What we use

• Session identifier. A random value in your browser's storage so repeated events in one visit can be grouped. It contains nothing about you.
• Return-visit flag. A simple marker so we can distinguish new from returning visits in aggregate.

Advertising

This site is designed to carry display advertising supplied by Google AdSense. Advertising is not switched on until a publisher account is approved and configured; while it is off, no advertising script loads and no advertising cookie is set.

When advertising is live, Google and its partners may use cookies or similar identifiers to serve and measure ads, including personalised ads where you have consented. You can review and change your Google ad settings at adssettings.google.com, and opt out of third-party vendor cookies at optout.aboutads.info.

Your choice, and how to change it

The first time you visit, a banner asks whether you accept advertising and measurement cookies. Until you press Accept all, advertising storage, ad personalisation and measurement storage are all set to "denied" using Google's consent signals, so no personalised advertising cookie is used. Choosing Reject non-essential keeps them denied; any advertising shown stays non-personalised.

Your choice is stored on your own device only. You can change it at any time using the Cookie settings link in the footer of every page.

What we do not use

We do not run cross-site profiling of our own, and we never pass any figure you type into a calculator to an advertiser. If our use of cookies changes materially, we will ask for consent first and update this page.

Clearing storage

Clearing your browser's site data for this domain removes everything described above. Nothing on the site stops working as a result.