Costco Wholesale’s sales soared in March, but not as much as expected: Curbs the retailer placed on its operations to cope with coronavirus-related demand slowed the pace in the back half of the month.

The retailer’s comparable U.S. sales excluding fuel — a key metric watched by analysts — rose 12.1%, it said Wednesday, well below the 24.1% average estimate compiled by Consensus Metrix. Limits on customer traffic, store hours and the closure of some departments put a damper on growth in recent weeks, the company said on a prerecorded call.

It was still the biggest monthly gain in at least seven years, according to data compiled by Bloomberg, and tops the 11.6% growth Costco posted last month. February sales were also aided somewhat by virus-fueled demand. The top-selling category in March by far was food, up about 35%, while sales of general-merchandise items like apparel, luggage and lawn and garden declined, Costco said on the call.

Costco, along with Walmart, has been one of the primary beneficiaries of consumer stockpiling in recent weeks as housebound shoppers scoop up toilet paper, cereal and other everyday essentials. Sales in Walmart’s U.S. stores rose 17% over the past four weeks, according to internal documents seen by Bloomberg. Both stores have taken steps to keep customers and employees safe, such as checkout-line markers to maintain distance between shoppers and limits on how many shoppers can enter a store at one time.

Compared with Walmart, though, Costco’s locations are more concentrated in coastal areas hardest-hit by the coronavirus, according to analysts at UBS. One-quarter of Costco’s locations are in markets highly exposed to the coronavirus, UBS found. Rival BJ’s Wholesale Club was slightly higher at 26%, while Walmart and its Sam’s Club warehouse chain had only 9% of its stores in hard-hit areas.

©2020 Bloomberg L.P.

More on the coronavirus outbreak

How is this outbreak affecting you?

What has changed about your daily life? What kinds of discussions are you having with family members and friends? Are you a health care worker who's on the front lines of the response? Are you a COVID-19 patient or do you know one? Whoever you are, we want to hear from you so our news coverage is as complete, accurate and useful as possible. If you're using a mobile device and can't see the form on this page, click here.