Amazon’s fourth-quarter earnings report, posted Thursday, showed how the growth of Jeff Bezos’ creation continues, driven by its increased dominance of the e-commerce landscape and by a flourishing cloud-computing business that now runs at the rate of $14 billion a year. .

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Amazon.com collected $136 billion in sales in 2016, a 27 percent bump that has led it to eclipse, for the first time, crosstown rival Costco Wholesale.

But the withering effects of a strong dollar on the value of overseas business and a slowdown in the growth of shipping revenue took some wind out of the e-commerce giant’s sails during the key holiday season, disappointing Wall Street’s lofty hopes and causing shares to slide by more than 4 percent to $805.10 in after-hours trading.

Amazon’s fourth-quarter earnings report, posted Thursday, showed how the galloping growth of Jeff Bezos’ creation continues, driven by its increased dominance of e-commerce landscape and by a flourishing cloud-computing business that now runs at the rate of $14 billion a year.

So do its investments in new warehouses and the personnel to man them: The company had 341,000 employees worldwide at the end of 2016, not including contractors or temps, a 48 percent increase from the previous year. Chief Financial Officer Brian Olsavsky said that the company’s 20 percent growth in warehouse square footage in 2015 accelerated to 30 percent last year as it scrambled to build new warehouses to handle an avalanche of products. Much of the increase in head count is from staffing of those centers, he said.

But even that head-turning growth fell short of analyst expectations for the holiday quarter, a shopping frenzy that constitutes most retailers’ busiest period.

For that quarter, Amazon posted sales of $43.7 billion, a 22 percent increase from last year. Analysts expected an average of $44.68 billion, a 25 percent increase.

A big part of the miss was the rising value of the U.S. dollar. A beefy greenback makes sales in foreign currencies worth less. About a third of the company’s retail sales are outside of North America.

Amazon said that if it were to exclude foreign-exchange effects, its total revenue would have been $558 million higher, a 24 percent overall increase and much closer to the market’s expectations.

CFO Olsavsky called that 24 percent rate “very solid, and we’re pleased with it.”

Analysts with GlobalData Retail saw another sign of concern: a slowdown in shipping-related revenue, which grew by 29 percent, versus 44 percent in the third quarter and 37 percent a year ago.

Shipping costs, in comparison, grew by 35 percent to $5.6 billion. That means an erosion in profit margins that could grow as Amazon doubles down on delivery.

“Arguably, low cost and fast delivery are a fundamental part of Amazon’s appeal to consumers. However, they are also its Achilles’ heel — and with Prime becoming more popular, and with a greater focus being put on speedier shipping times, we have concerns that Amazon could see further profit erosion as it enters its new fiscal year,” wrote the GlobalData analysts.

Profit, meanwhile, was much higher than expected, at $749 million, or $1.54 per diluted share, versus $482 million a year ago. Analysts were expecting $1.35 per share in profits.

The foreign-exchange impact on Amazon’s operations is forecast to continue into the first quarter of 2017, in which the company expects a $730 million hit.

That impact combined with the continuation of a major ramp-up in investment that began in the second half of 2016 as Amazon reinforced its video content, fulfillment and data-center operations. They led Amazon to post an operating-income forecast of $250 million to $900 million for the quarter, versus $1.1 billion in the same period last year.

Olsavsky said Amazon will continue to invest in India, in the Alexa voice-activated artificial-intelligence ecosystem, and in additional benefits to make the Prime loyalty program more attractive.

Amazon also is further branching out into the world of brick-and-mortar retail. The company recently opened an experimental grocery store in Seattle, dubbed Amazon Go, where there are no cashiers. Located on the company’s downtown campus, it’s only open to certain Amazon employees, but is expected to open its doors to the public sometime in the next few months.

Amazon also has three bookstores in the U.S. (The first one opened in 2015 in Seattle’s University Village shopping center.)

Olsavsky said that Amazon could add five more bookstores this year. “The bookstores,” he said, “are really a great way for customers to interact with our devices.”

Amazon shares closed the regular trading day at $839.95, up $7.60.