Behind the data

This topic is the site explaining itself: where the numbers come from, what they mean, and how far the history behind them reaches.

We check the shopping portals we compare (a portal is a site that pays you for starting your purchase there), each on its own schedule, read the rates from their own pages, and record what changed. Over time that becomes a history, and the history is what every "is this rate good?" verdict is measured against. A rate is only good or bad next to what that store usually pays on that portal, which is the one thing a plain list of rates cannot tell you.

The posts here cover how the verdict math works, and why a rate counts for more when it held for eighty days than when it flashed for one. What "up to" rates do to a comparison. Why one portal can state one offer in percent and the next in dollars, and why that difference is part of the rate rather than a formatting detail. How a rate we could not confirm gets a label saying so. There is also the founding story, which is mostly an account of not knowing whether 6% was any good.

Full transparency, since it shapes everything in this topic: the rate history starts in early July 2026. It gets more useful every week it runs, and where a store has barely any history behind it, the site says so rather than dressing up a thin number.