NEW YORK, United States — Shopify Inc. easily beat revenue estimates for the key holiday shopping period, but a decline in the growth rate for business done on its platform tempered the otherwise positive results.Overall revenue surged 71 percent to $222.8 million in the fourth quarter, beating the Wall Street consensus of $209.48 million. However, growth in gross merchant volume, the amount of money generated by Shopify users, slowed, signaling fewer new merchants and consumers are using the site.The shares fell 3.5 percent to $132.77 at 10:39 a.m. in New York. They have more than doubled in the past year.Shopify rocketed out of its initial public offering in 2015, beating growth estimates quarter after quarter. It hit some snags last year though, when short seller Andrew Left of Citron Research raised doubts about the sustainability of many of its small-business users. Investors have begun to pay more attention to gross merchant volume and whether revenue is coming from larger, more sustainable businesses or the small merchants that make up the bulk of Shopify’s users.Shopify plans to expand into new non-English-speaking markets in 2018, focusing initially on Japan, Singapore, France and Germany. Despite rising concerns about growth, the company says the total possible market for its services keeps changing and expanding as it comes up with new products and retail continues to rush online.“That gets proven day in, day out,” Chief Financial Officer Russ Jones said on a conference call Thursday.Shopify Plus, which counts sales from Shopify's largest customers, contributed 21 percent of monthly recurring revenue, compared with 17 percent at the end of 2016. The company said it expects full-year revenue of as much as $990 million, well ahead of the $957.1 million analysts had projected. Earlier this month, Canada's most populous province chose Shopify to run its online marijuana sales when the drug becomes legal later this year.Gross merchant volume was $9.1 billion in the fourth quarter, a 65 percent increase from a year earlier, but a slower pace than the 69 percent increase in the third quarter.Shopify posted a profit excluding some costs of 15 cents, higher than the 5 cents analysts predicted.By Gerrit De Vynck with assistance from Karishma Motwani and Bharathi Ramji; Editors: Jillian Ward, Molly Schuetz, Jessica Brice.