Small Business

Don't ask McDonald's CEO this. He's not talking

What's really driving McDonald's higher?

McDonald's all-day breakfast has only been in place for a couple weeks, and Wall Street is eager to know how it's impacting the fast food giant's sales. But the Golden Arches isn't willing to shed much light on its performance—at least, not yet.

"Totally understand the interest, but it's just too early," said CEO Steve Easterbrook on the company's earnings call.

Earlier in the day, the chain delivered stronger-than-forecast results that topped estimates. It also snapped a streak of declines in domestic same-store sales, sending shares to record levels. That period did not include the nationwide all-day breakfast debut, a much-touted initiative for the chain's turnaround efforts.

Breakfast sales, especially those of the McMuffin, helped contributed to the beat. After the chain transitioned back to the sandwich's original recipe with butter instead of margarine, it saw a double-digit increase in its sales.

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Easterbrook provided relatively few details on all-day breakfast's performance so far – despite multiple analyst questions about it on the call.

He stressed the support for it among the operator community.

"The enthusiasm levels from customers and teams in restaurants are high. It's been a successful rollout," he said, adding that it has been smoother operationally than "people had feared."

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With the initiative is still in its infancy nationwide, Easterbrook said it's too "early days" to get a real read on sales though the chain is encouraged by what it has seen so far.

"I really don't want to give too much guidance on it—not to be evasive," he said.

Anecdotally though, he said college towns are seeing a lot of activity during extended breakfast hours, adding that it has been "cultish" among students.