FuboTV grew its internet pay-TV subscriber rolls at a rapid clip last year — and sustained heavy losses to get there.

The company ended 2020 with 547,880 subscribers, up 73% year-over-year. It gained 92,800 net new subscribers in the fourth quarter, an increase of 237% year-over-year. FuboTV reported $217.7 million in revenue for the year, with almost half of that ($105.1 million) in Q4 of 2020.

Total net loss for last year was $570.5 million (including a $248.9 million charge for impairment of intangible assets and goodwill), compared with a net loss of $35.0 million for 2019. Over the same time frame FuboTV’s operating loss grew more than 12-fold, to $479.9 million for full-year 2020, versus $38.9 million a year earlier.

Meanwhile, FuboTV expects to lose subscribers in the first quarter of 2021, projecting 520,000-530,000 subscribers by the end of March, a sequential decline of 3%-5%. On a full-year basis, the company expects revenue of $460 million-$470 million and anticipates ending 2021 with 760,000-770,000 subscribers.

Despite the widening losses, FuboTV expects to turn the corner to become profitable with a two-part strategy: generating higher ad revenue per subscriber going forward through better targeting; and introducing sports betting to the TV platform as a new revenue stream.

The company’s goal is to develop FuboTV “into a new kind of media company that combines streaming video and interactive sports wagering,” CEO David Gandler and executive chairman Edgar Bronfman Jr. wrote in a letter to shareholders. “We believe our sports-focused differentiated position will allow us to continue to grow our business across KPIs, including advertising.”

In after-hours trading Tuesday, Fubo TV shares were down more than 6%. The stock price more than doubled in December 2020 after a bullish analyst upgrade, before falling precipitously on skepticism from Wall Street analysts at LightShed Partners about FuboTV’s prospects. In 2020 to date, the share price was up about 50% as of market close March 2.

FuboTV recently closed the acquisition of sports betting and interactive gaming company Vigtory, which “allows us to accelerate the launch of our owned-and-operated sportsbook,” the execs said in their shareholder letter.

The company plans to launch free-to-play predictive games in the third quarter of 2021 (first to FuboTV subscribers and later to all consumers) and set a Q4 launch for Fubo Sportsbook, for which the company has agreements with Major League Baseball and the National Basketball Association to become an “authorized gaming operator.” The company also secured its first market-access deal for Fubo Sportsbook in Iowa through Casino Queen.

“Ultimately, we intend to integrate Fubo Sportsbook into FuboTV’s live TV streaming platform for a seamless viewing and wagering experience,” Gandler and Bronfman Jr. wrote.

FuboTV uses a proprietary metric — adjusted contribution margin — to try to show that its virtual pay-TV business is improving its profitability. That metric was positive 11.7% in Q4 of 2020, up from 0.7% in Q4 2019.

The company calculates adjusted contribution margin by taking average revenue per user (ARPU) and subtracting average cost per user (ACPU), defined as subscriber-related expenses minus minimum guarantees expensed, payment processing for deferred revenue, and other subscriber-related expenses in a given period, divided by the average daily subscribers in the period and then divided by the number of months in the period. However, that excludes costs like sales and marketing, broadcast and transmission, and technology and development — meaning that on an operating basis, even excluding one-time charges, FuboTV’s subscription-television business runs at an operating loss.

In 2020, FuboTV users (paid and trial) streamed over 544.9 million hours, an increase of 82% over the prior year. That translates to active subscribers watching 7.2 hours per day, up from 6.4 hours in 2019.

New York-based FuboTV went public last October after merging with FaceBank Group, a tech company that created digital likenesses of celebrities and sports stars. The legacy FaceBank business reported no revenue in Q4 2020.