The Sandwich Became an Official Economic Indicator — Twice, in Two Different Countries

A national statistics office tracks the weekly till receipts of a sandwich chain and publishes the result as an official economic indicator. That isn’t a metaphor or a joke headline — it’s a real, ongoing data series. And Britain isn’t even the only country doing it with a sandwich.

The Pret Index: sandwiches as a proxy for the whole economy

During and after the pandemic, the UK’s Office for National Statistics started tracking weekly transaction data from roughly 400 Pret A Manger stores around the country, publishing it as one of its “real-time indicators” of economic activity. Bloomberg built a running graphic around it, because the logic is genuinely sound: Pret shops cluster around financial districts, office towers, and train stations. When people go back to commuting, back to the office, back to city-center foot traffic, they buy more egg-and-cheese sandwiches on the way in. The till data moves before the slower official statistics catch up — which makes a sandwich chain’s daily sales one of the fastest, cheapest ways to sense whether a city’s economy is actually breathing again.

France runs the identical trick with a different sandwich

Cross the Channel and the same idea shows up wearing a beret. France’s most iconic sandwich, the jambon-beurre — ham, butter, baguette, nothing else, a formula essentially unchanged for over a century — has become its own informal cost-of-living gauge, sometimes called the Jambon-Beurre Index. Its price is watched the way other countries watch a basket of staple goods, precisely because it’s cheap, standardized, and bought constantly. The scale backing that attention is real: an estimated 3.1 billion sandwiches were consumed in France in 2025, with the jambon-beurre still the single most sold variant — something in the range of three million of them sold every single day nationwide.

Two countries, two completely different sandwiches, the same underlying reasoning: find the food item people buy constantly, at a near-fixed format, across every income bracket, and its price and volume will tell you something true about the economy faster than almost anything else being measured.

Why a sandwich, specifically, works as an indicator and a dinner reservation doesn’t

The mechanism is simple once you see it. A restaurant dinner is planned, discretionary, and infrequent — a bad month barely moves the number of times someone eats out. A sandwich bought on the way to work is none of those things: it’s habitual, cheap enough to not think about, and tied directly to whether someone is physically commuting into a city center at all. That combination — high frequency, low price, and a near-universal daily ritual — is exactly what makes a category “boring” for a chef and fascinating for an economist. It moves in near real time, and it moves for almost everyone.

The origin story everyone tells is probably wrong

Here’s the reveal that tends to surprise people: the classic story of the Earl of Sandwich inventing the format at a card table — too absorbed in gambling to put his fork down, ordering meat between bread so he could eat one-handed — is almost certainly a myth. The historical record shows John Montagu, the 4th Earl of Sandwich, was a busy Navy administrator and cabinet minister who routinely ate at his desk because he worked constantly — not because he was gambling. The earliest documented use of “sandwich” as a food term, from historian Edward Gibbon’s journal in November 1762, predates the gambling anecdote appearing in print by roughly a decade. The practice of eating cold meat between bread was already common in London coffeehouses and clubs; what the Earl actually contributed was his name attached to something fashionable people were already doing. Even the sandwich’s own origin story turns out to be a case of the wrong explanation surviving because it’s a better story than the true one.

It didn’t stay Anglo-French for long

The format traveled and got reinvented everywhere it landed, and one of the clearest examples is genuinely global. French colonists brought the baguette to Vietnam in the mid-19th century; by the 1950s, street vendors in Saigon had rebuilt it entirely — a shorter, thinner-crusted loaf packed with pork, pâté, pickled daikon and carrot, cilantro, chili. Bánh mì spread worldwide after 1975, carried by Vietnamese refugees resettling across the US, France, Australia and Canada — a food history we’ve covered in more depth in how Vietnam War refugees carried banh mi and pho to America. The dish’s global arrival got a formal marker in 2011, when “banh mi” was added to the Oxford English Dictionary — official recognition that a Saigon street-food reinvention of a French colonial import had become its own permanent, internationally recognized category.

The mass-market engine: the UK meal deal

Zoom back out from the history and the indicators, and the everyday commercial scale is just as striking. More than a third of Britons buy a meal deal — sandwich, snack, drink, for a fixed price — at least once a week, with roughly seven million sold on an average weekday. Boots launched the format in 1999 at 16 UK stores for £2.50; it’s now standard across supermarkets, pharmacies and bakery chains nationwide. Greggs, a bakery chain built substantially on sandwich-format food, reported sales up 7.5% to £800m in the first 19 weeks of 2026 alone — during a period when household budgets were under real pressure, which is exactly when a fixed-price sandwich-and-a-drink format tends to gain, not lose, ground.

Why this actually matters for anyone costing one

All of this points at the same operational fact: sandwiches are not a minor menu category anymore, if they ever were — they’re one of the highest-volume, lowest-margin-per-unit food formats that exists, sold in the millions daily on a near-fixed recipe. That combination is exactly the one where small errors get expensive fast. A gram of ham drifting off spec on a jambon-beurre sold three million times a day, or a supplier’s pack-size abbreviation misread on the mayonnaise line, doesn’t cost you once — it costs you at the same rate the sandwich sells. We’ve written about both halves of that problem already: what happens when “one portion” is left as a vague instruction instead of a number, and what happens when a supplier’s “PC” or “CS” gets guessed instead of confirmed. A sandwich sold at commuter volume is the sharpest possible version of both problems at once — high frequency turns a small, silent error into a real one within days, not months.

Related reading

• How Vietnamese refugees carried banh mi and pho across the US, France, Australia and Canada after 1975.
• Why ‘one portion’ as a spoken instruction produces three different plates from three different cooks — and what to write down instead.
• The supplier-abbreviation chaos — PC, PAK, CS, KG — that silently wrecks food cost by whole multiples, not a few percent.

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Sources

• Transactions at Pret A Manger — Office for National Statistics
• What the Pret Index Told Us About the Economic Recovery — Bloomberg
• The Jambon-Beurre Index: Economy in a Sandwich — Fine Dining Lovers
• Statistiques : Consommation de sandwichs en France — Planetoscope
• Le sandwich le plus vendu en France ? Jambon-beurre — Accio
• Did the 4th Earl of Sandwich Really Invent the Sandwich? — History Hit
• Bánh mì — Wikipedia
• Meal deal — Wikipedia
• Greggs increases meal deal prices again but insists ‘value is where we’re focused’ — The Grocer