Why did U.S. inflation shake markets without sinking the dollar?

4.2 per cent was the number that put traders on alert: U.S. consumer prices rose at their fastest annual pace in three years in May. The figure matched economists’ expectations, which mattered almost as much as the increase itself. Instead of triggering a rush into the U.S. dollar, the report left markets recalibrating the odds of another Federal Reserve hike while watching energy prices, geopolitical risk and Canada’s own rate path.

The Bottom Line

• U.S. CPI rose 4.2 per cent year over year in May, the largest annual gain since April 2023.
• The reading matched economists’ forecasts, reducing pressure for an immediate Federal Reserve rate hike.
• The dollar index slipped 0.2 per cent to 99.75, close to Monday’s two-month high of 100.214.
• The Canadian dollar gained 0.2 per cent after the Bank of Canada held its benchmark interest rate unchanged.
• Energy prices and U.S.-Iran tensions kept traders cautious, with inflation risk still tied to gasoline and other energy costs.

Breaking It Down

The May inflation report landed in a market already braced for movement. Before the release, traders were focused on whether headline CPI would rise above the 4.0 per cent level for the first time since May 2023, while core CPI was expected to rise 0.3 per cent month over month and 2.9 per cent year over year. Those expectations had helped support the dollar in the run-up to the data, as investors priced in the possibility that the Federal Reserve could respond to a fresh inflation shock.

Once the figures arrived, the message was more complicated. Inflation was hot, but not hotter than expected. The May CPI report showed consumer prices rising 4.2 per cent over 12 months, driven in part by gasoline and other energy products linked to Middle East conflict. That kept the inflation story alive, but it did not deliver the upside surprise that would have forced traders to rapidly reprice the next Fed move.

Karl Schamotta, chief market strategist at Corpay in Toronto, framed the shift clearly.

Underlying inflation avoided a widely feared acceleration last month, suggesting that soaring energy prices are not—yet—feeding into the core measures targeted by the Federal Reserve

That distinction matters. Headline inflation captures what households feel immediately at the pump and in energy bills. Core inflation, which strips out more volatile items, is watched closely because it can reveal whether price pressure is spreading deeper into the economy. Traders of short-term U.S. interest rates edged away from bets on a September Fed hike, while still showing strong conviction that a hike could arrive by October.

CPI

The Consumer Price Index tracks changes in prices paid by consumers for goods and services.

Core CPI

A measure of inflation that excludes more volatile categories and is closely watched by central banks.

Dollar index

A gauge of the U.S. dollar against a basket of six major currencies.

Why This Matters

For Canadians, the story runs through the exchange rate. A softer U.S. dollar helped the Canadian dollar advance 0.2 per cent against its U.S. counterpart. That move came after the Bank of Canada left its benchmark interest rate unchanged, while Governor Tiff Macklem reiterated that the central bank would not hesitate to raise rates if needed to keep inflation in check.

The effect is practical. A stronger loonie can ease the cost of U.S.-priced imports and travel, while a weaker one can do the opposite. But currency markets are not moving on Canada alone. The U.S. inflation path still influences global borrowing costs, commodity prices and investor appetite for risk, all of which feed back into Canadian households and businesses.

Geopolitics added another layer. The U.S.-Israeli conflict with Iran kept traders on edge, while U.S. President Donald Trump said Iran had taken too long to negotiate and would now “have to pay the price.” Tehran said it would reassess diplomatic engagement with Washington after overnight tit-for-tat strikes. That tension matters because energy prices helped push headline inflation higher, and another jump in oil or gasoline could change the inflation debate quickly.

What Comes Next

The next confirmed focal point is the Federal Reserve meeting next week. Traders are positioning for a more neutral statement from officials, while still weighing whether inflation and energy costs could justify a hike later this year.

Currency traders are also watching Japan. A Bank of Japan rate hike at its June 16 policy meeting is nearly fully priced in, while the yen remains near 160 per U.S. dollar, a level widely viewed as sensitive for possible official intervention.