Allbirds said Tuesday that its third-quarter revenue rose 33% from last year, while its losses widened as the cost of opening stores and listing its stock weighed on its results.

Allbirds shares fell 4% in extended trading on the report, which was its first as a public company.

For the three months ended Sept. 30, net losses widened to $13.8 million, or 25 cents per share, from a loss of $7 million, or 13 cents a share, a year earlier.

Sales climbed 33% to $62.7 million from $47.2 million a year ago. The sustainable shoemaker said its revenue was up 40% on a two-year basis.

Co-founder and CEO Joey Zwillinger said the company saw notable strength in its stores in the United States. Shoppers also responded well to product launches, including a recently debuted performance apparel line.

Selling, general and administrative expenses were $33.0 million, or 52.6% of revenue compared with 42.5% of revenue for the same period in 2020. Costs related with four new store openings and hiring more employees contributed to the uptick, it said.

Allbirds shares are down slightly since the company went public on Nov. 3. The stock closed Tuesday at $19.24, about 9% below its opening trade price of $21.21.

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