China’s cooling economy may have sent some chill into coffee cups. Starbucks, the world’s largest coffee chain, said its same-store revenue rose 1% for the quarter ended Dec. 31 as higher prices made up for lower coffee sales.

The marginal revenue gain compares with an 8% jump in the previous quarter and a 6% increase in the same period a year ago. The number of transactions fell 2%, according to the company’s earnings report.

The U.S. coffee chain added almost 600 stores in China in the past year, bringing the total to 3,684. Starbucks faces growing competition in China from domestic rivals such as Luckin Coffee.

But Starbucks remained upbeat about prospects in China, which is now the world's biggest coffee market. The company said it plans to almost double the number of stores in the country to 6,000 over the next four years.

Globally, Starbucks’ revenue rose 9.2% to $6.63 billion, topping the consensus forecast, mainly driven by a record $4.6 billion in North American sales. Starbucks shares rose 3.4% in early trading Friday.

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