Skechers USA Inc.’s stock plunged 30 percent after the Manhattan Beach footwear firm announced quarterly profits that failed to meet Wall Street expectations.

Skechers announced net earnings of $66.6 million (44 cents a share), a 30.3 percent increase from the same period a year earlier. Despite this growth, net sales were $856.2 million, disappointing analysts who had predicted $877 million in sales.

The stock was trading at $31.50 Friday afternoon, down from Thursday’s high of $46.15.

Skechers Chief Operating Officer David Weinberg blamed the unexpected third quarter performance on a lackluster spending environment at home and low exchange rates abroad, especially in Brazil, Canada and Chile. Still, he remained optimistic.

“Though we believe the sluggish macro domestic retail environment and declining currency in several key markets had an impact on our net sales, the third quarter was still a sales record,” he said in a statement accompanying the earnings.

Skechers also had extra legal fees during the quarter that reduced its earnings per share by 15 cents.

Weinberg said Skechers plans to expand its retail footprint to boost sales, with as many as 17 new stores to open by the end of the year.