Janiel McEwan | How a global price becomes a local one

A woman in a Montego Bay supermarket taps her card and watches the total come back higher than she expected, not dramatically, just enough to make her check the receipt twice against a basket of groceries she buys most months of the year.

The explanation for that number did not begin at the register, and it did not begin in Jamaica. It began in a wheat field battered by heat on the American Plains, in a Ukrainian port under fire, in a cane field in Brazil running short on rain, and in a currency market thousands of miles from where she is standing.

This is the story of how that distance closes, of how weather, war and shipping schedules on the other side of the world quietly become a number on a Jamaican receipt.

That story, this year, has been an unusually eventful one.

The United Nations Food and Agriculture Organization’s Food Price Index, the benchmark for tracking what a basket of globally traded food commodities actually costs, averaged 133.3 points in August, up 1.9 per cent from July and 2.5 per cent higher than a year earlier. It was the highest reading since the end of 2022.

Every one of the five commodity groups the index tracks – cereals, sugar, vegetable oils, dairy and meat – rose that month, which matters because it tells you this was not one crop having a bad season. It was a basket-wide movement, the kind that shows up in more than one aisle at once.

Grain led that basket-wide move, and grain is where this story properly begins.

The Cereal Price Index rose 2.2 per cent to 116.3 points, its highest level since May 2024, with world wheat prices up 2.6 per cent on the month and 15.0 per cent above a year earlier, largely on continued disruption to Black Sea export routes.

World maize prices rose 2.5 per cent, pressured by deteriorating yield prospects in the American Corn Belt and in parts of the European Union after prolonged heat, alongside strong demand from ethanol and feed buyers.

Sugar moved harder still in percentage terms, the FAO Sugar Price Index jumping 11.9 per cent in August alone to its highest level since June 2025, on weaker expected sugar beet yields in the European Union, concerns over El Niño’s effect on Asian cane production, lower output from Brazil and India’s decision to allow duty-free raw sugar imports in response.

But it is grain, wheat and maize above all, that sits underneath the widest share of what Jamaica actually imports and processes – flour, bread, animal feed and the raw inputs behind a long list of packaged goods on a Jamaican shelf.

STATIN trade data show cereals and cereal preparations among Jamaica’s largest food-import categories, with wheat and maize accounting for the bulk of that raw material. That is why grain’s movement carries more weight in this story than its raw percentage change alone would suggest.

FUTURES MARKETS

The futures markets that actually set these prices day to day moved even further and faster than the FAO’s monthly index captures, because futures markets are forward-looking in a way a monthly survey cannot be.

Wheat on the Chicago Board of Trade climbed to nearly US$7.90 a bushel in the last week of August, its highest level since February 2023, a rally driven largely by a sharp escalation in attacks on Ukrainian port infrastructure and shipping lanes in the Black Sea.

Corn, moving for entirely different reasons, climbed past US$5.50 a bushel by mid-September, its highest level since July 2023, after the US Department of Agriculture cut its yield forecast in its August report and cut it again as crop conditions deteriorated through the season.

By September, the USDA was projecting a shortfall of nearly 30 million tonnes between global corn production and consumption for the 2026/27 season, the largest such gap in more than three decades.

This distinction, between an event and the market’s expectation of an event, is worth sitting with, because it explains why prices move before anyone can confirm a shortage is real.

A trader pricing next season’s wheat is not pricing the harvest that already happened. He is pricing the one that has not happened yet, adjusting a number on a screen based on a drought forecast, a shipping report from a war zone, or a crop tour’s field notes, weeks or months before a single truck of grain moves.

Fear of a bad outcome moves a price almost as effectively as the bad outcome itself. By the time the actual harvest numbers are confirmed, the price has usually already done most of its moving, which is exactly why a Jamaican shopper can feel the effects of a shock that, technically, has not even finished happening yet.

A biscuit, a loaf, a bag of animal feed or a bottle of cooking oil can be entirely local in every way that matters to the naked eye, made in a Jamaican factory, by Jamaican workers, sold by a Jamaican company, and still be exposed, completely, to a price set on an exchange in Chicago or Rotterdam.

The flour, the raw sugar, the vegetable oil going into that product is bought on an international market at an international price, in US dollars. A Jamaican address on the finished product does not move the field where the wheat grew or the refinery where the oil was pressed. It only adds a local chapter to a story that started somewhere else entirely.

THE EXCHANGE RATE

Then there is the exchange rate, which does not simply pass a global price through unchanged, it actively resizes it. Over the week of September 11-16, the Jamaican dollar traded against the US dollar in a narrow band between roughly J$157.42 and J$157.99, a level the Bank of Jamaica has been actively defending, intervening in the market on September 17 with a US$40 million sale to authorised dealers and cambios through its B-FXITT programme.

Consider what that rate actually does to an imported input. A commodity priced at US$100 costs a Jamaican importer roughly J$15,750 at the lower end of that band and roughly J$15,800 at the higher end, a difference that looks trivial in isolation. But when the underlying US dollar price of that same commodity has already climbed, say wheat rising from roughly US$5.90 to US$7.84 a bushel since June, a rise of about 33 per cent, the exchange rate is no longer adjusting a stable number. It is amplifying a number that was already moving.

A Jamaican importer buying that wheat in September is absorbing the commodity’s rise and the currency’s conversion cost simultaneously, two separate pressures landing in the same invoice, even though the consumer at the end of the chain will only ever see one final price.

To make the mechanism concrete, take a simplified, illustrative example rather than any single company’s actual figures.

Suppose a Jamaican manufacturer needs a shipment of wheat priced at US$300 a tonne on the international market. Convert that at roughly J$157.70 to the dollar and the raw commodity alone lands at close to J$47,300 a tonne before a single Jamaican worker has touched it.

Add freight and insurance, port handling, and financing on the sixty-odd days many importers extend to their own customers, and the landed cost climbs further before processing even begins. Milling, packaging, wages, and overhead add another layer.

A wholesaler then prices in his own margin, covering the risk of extending credit and the cost of holding inventory, before a retailer adds a further markup to cover rent, staffing and the cost of everything else on the shelf around that one product.

None of these additions is unreasonable on its own. Stacked together, they are the difference between a US$300 commodity and whatever number eventually appears on a Jamaican receipt.

How much of what shows up on a Jamaican receipt is genuinely explained by what happened in a wheat field or a shipping lane, and where does the explanation stop being global and start being domestic?

THE GLOBAL STORY

On the food side of the ledger, the evidence points mostly toward the global story.

Jamaica’s Food and Non-Alcoholic Beverages division rose 1.5 per cent in August 2026 alone, the largest single driver of that month’s headline inflation, a movement consistent with the cereal and sugar pressures documented above.

It is worth noting, in fairness, that not every line on a Jamaican CPI receipt traces back to a commodity exchange. July’s inflation was actually led by a domestic route taxi fare adjustment rather than food. But grain is the dominant thread running through this particular story, and the chain traced above, from a Kansas wheat field to a Jamaican shelf, is the one actually setting the cost of flour, bread, feed and the dozens of products built on them.

Even where global commodity prices are genuinely the driver, they rarely arrive on the same day the shock occurred.

Contracts get negotiated ahead of time, sometimes months ahead, locking in terms that reflect the market conditions of the day they were signed. Shipments take real, physical weeks to cross an ocean. Processing, milling, packaging, distribution, each adds its own stretch of time before a product reaches a shelf.

What can be said with confidence is that the lag is real, that it is measured in weeks and months rather than days, and that it is one of the main reasons a shopper can feel a price increase for a shock that made headlines, and disappeared from them, long before the receipt ever changed.

The woman in the supermarket does not experience any of this as a chain. She experiences a total that came back higher than she expected, on a Tuesday, for reasons that were never going to be printed on her receipt no matter how long she stands there looking at it.

What she is holding, once you trace it back, is a wheat field in Kansas and a shipping lane near Odessa and a currency the Bank of Jamaica spent US$40 million defending in a single week and a route taxi fare that changed on the first of July for reasons that have nothing to do with any of that.

The number is real. So is the distance behind it. Understanding that distance will not make the total any smaller. But it replaces confusion with something more useful – a reason, several reasons actually, arriving late, the way these things always do, and landing all at once in a single, ordinary grocery bill.

- Janiel McEwan is an Economist and Researcher. Email feedback to columns@gleanerjm.com. ONLINE ONLY COMMENTARY.