THIS WEEK · NORTH AMERICA

Co-owners,

Fitting timing: in the week we profile a company that has spent a century rebuilding engines, 90 Percent got an overhaul of its own. The newsletter has a fresh look, and so does get90percent.com, where every company we’ve covered now sits in one easy-to-browse archive. Hit reply and tell us what you think.

We've spun the wheel for the North America bucket. The ticker has landed on a company from small-town Indiana that has been building engines since before the Wall Street Crash, and now finds itself in the least glamorous corner of the AI story.

Before we dive in, a reminder of what the index itself has delivered over time.

There is a good chance you have seen the name without registering it. It is stamped on the engine block of a Ram heavy-duty pickup, on the side of a delivery lorry, on a generator humming outside a hospital. Cummins makes the thing that turns fuel into motion, and it has been doing it for more than a century. Almost nobody buys a Cummins directly. You buy the truck, or the bus, or the building, and Cummins is inside it.

If you hold a world equity index fund, you own a slice of it. And lately that slice has been doing something unexpected: helping to power artificial intelligence.

Cummins began with a bet between two men who could not have been less alike. Clessie Cummins was a self-taught mechanic from Indiana with an eighth-grade education, a gift for engines, and a job as chauffeur to a wealthy local banker named William Irwin. In 1919, Irwin put up the money and Clessie put up the skill, and together they bet that Rudolf Diesel's heavy, smoky engine, then twenty years old and used mostly in factories and submarines, could be made small and reliable enough to move things.

It took years. The early engines flopped. The breakthrough came in 1933, when a Cummins diesel proved itself in small railway locomotives, and from there the company grew into the leading independent engine-maker in North American trucking. It has supplied engines to the truck-builder PACCAR, still its largest customer, for eighty-one years without a break.

The company is split into five parts, and it is worth knowing what each one does.

Engine is the historic heart: diesel and natural-gas engines from 2.8 to 15 litres, powering everything from pickups and delivery vans to heavy lorries, buses and construction machinery. A new generation, badged X15 and built to run on more than one fuel, arrives for the 2027 emissions rules.

Components makes the parts that bolt onto the engine. Turbochargers, the emissions-cleaning kit that sits in the exhaust, and, since a 2022 acquisition, the axles, drivelines and brakes underneath the truck. Its automated gearboxes come through a joint venture with Eaton.

Distribution is the least visible and, by revenue, the largest: a global network of around 640 distributor locations and more than 13,000 certified dealers, selling parts and fixing machines in roughly 190 countries. It is the steady, repeat-business backbone, and the channel that gets generators to data-centre customers.

Power Systems builds power generation, from small standby units up to 3.5-megawatt machines, plus the very large engines used in mining, rail and shipping. This is the part now riding the AI wave.

Accelera is the newest and smallest: the zero-emissions arm, making batteries, fuel cells, electric axles and hydrogen equipment.

Everyone knows AI runs on chips. Far fewer people think about what happens when the power to a data centre flickers. The answer is that rows of large diesel and gas generators kick in within seconds, because for a building full of billions of dollars of computers, going dark is not an option.

Cummins makes those generators, and demand has gone vertical. In the second quarter of 2026, its Power Systems revenue jumped 19% on the year before, driven above all by data-centre orders, and that business now earns a fatter margin than any other part of the company. Management has said it is taking generator orders that stretch years into the future. A company most people associate with lorries has become one of the two big names, alongside Caterpillar, keeping the AI build-out physically switched on.

At first glance 2025 looks like a down year: net profit fell from $3.9 billion to $2.8 billion. But that flatters 2024, which included a one-off gain of about $1.3 billion from spinning off Cummins' old filtration business, Atmus, as a separate listed company in March 2024. Strip the one-offs from both years and the underlying business actually earned more in 2025 than in 2024. Revenue held roughly flat at $33.7 billion, as strong power-generation demand offset a weak year for North American lorries.

One awkward line sits inside Accelera. Cummins spent years betting that green hydrogen would take off, and built a business making the electrolysers that produce it. In 2025, as that market arrived more slowly than hoped, the company wrote down roughly $458 million and pulled back. It is a rare public admission that a big bet had not paid off on schedule, and a reminder that even patient, century-old companies get the future wrong sometimes.

Worth noting too: in 2023 Cummins agreed to pay around $2 billion to settle US claims that certain pickup engines were set up to beat emissions tests. For a company whose whole reputation rests on engineering integrity, it stung.