Movement · this week

The deepest history in our corpus.

We've tracked cheddar for 5 weeks. The cheapest valid pick has held at $15.70/kg for 4 of them.

Cheddar is the deepest data we’ve got — 5 Fridays in a row of cheapest-valid-pick snapshots from both supermarkets. For 4 of those weeks the cheapest pick has held within 5% of itself at $15.70/kg. This is the credibility fact for the publication: how stable a number actually is on a real shelf, week after week, when nobody’s editing it. Five per cent is the band we use for "held flat" at this depth of history. Anything tighter and ordinary week-to-week noise starts firing false signals. As the corpus deepens we’ll tighten this band and replace the threshold with year-on-year framing.

How we measure this

We look at the staple with the longest snapshot history in our corpus and report how many of those weeks the cheapest valid pick has held within 5% of itself. Five per cent is the band we use for "held flat" at short-range history; it’ll tighten as the corpus deepens.

Read more

• Butter — weekly read →
• How we measure →

Kepie Watch · Issue ending Monday, 25 May 2026