Uber says its business is bouncing back from a pandemic-induced slump.

Uber said on Wednesday that growing revenue and returning passengers sent a strong signal that its business was bouncing back in the final three months of 2021 from the slowdown caused by the pandemic.

The quarter also provided another indication of how Uber’s fortunes rise and fall with its investments in other companies.

Uber’s revenue grew to $5.8 billion, an 83 percent increase from a year earlier, exceeding analyst expectations. The company also marked its second profitable quarter as a public company, earning $892 million largely from its investments in Grab, the Southeast Asian ride-hailing company that went public in December, and Aurora, the autonomous vehicle start-up.

Uber lost $968 million during the same period a year earlier and reported a loss of $2.4 billion in the third quarter of 2021 caused by its investment in Didi, the Chinese ride-hailing company.

Its investments in other ride-hailing companies would probably continue to cause fluctuation in its profits and losses, Uber said in its earnings report. Uber’s chief executive, Dara Khosrowshahi, said at a December analyst event that the company would hang on to some of its strategic investments but would eventually look to sell its stake in Didi.

Uber’s loss from operations for the quarter was $550 million, a 37 percent improvement from a year earlier.

Uber said it was attracting a growing number of users by relying on its food delivery business, Uber Eats, to bring in business during spikes in coronavirus cases, when its ride-hailing business declined. Uber reported 118 million users during the fourth quarter, a 27 percent increase from a year earlier.

“Our results demonstrate just how far we’ve come since the beginning of the pandemic,” Mr. Khosrowshahi said in a statement. “While the Omicron variant began to impact our business in late December, mobility is already starting to bounce back.”

The growth in users sets Uber apart from its primary rival in the United States, Lyft. In an earnings report on Tuesday, Lyft said it had 18,728 users during the fourth quarter, a 49 percent increase from a year earlier but a slight decrease from the third quarter. The modest decline in users showed that the winter wave of Omicron might have presented more challenges to Lyft’s business.

Still, Lyft said that its revenue had grown by 70 percent, to $969.9 million, and that its losses had improved to $258.6 million, a 43 percent change from a year earlier.

Analysts said Uber’s and Lyft’s businesses would most likely continue to fluctuate as travel was affected by the pandemic.

“It’s going to ebb and flow,” said Tom White, a senior research analyst with the financial firm D.A. Davidson. While Lyft’s business was tied to coronavirus conditions in North America, Uber could experience other issues because it operates around the world, he added.