Roku spiked 25 percent Monday after releasing preliminary numbers for its active accounts and streaming hours for its Q4 2018.

The company handily beat the FactSet consensus estimate of 6.6 billion streaming hours, reporting an estimated 7.3 billion, up 68 percent year-over-year, according to a press release. That brings streaming hours for 2018 up to roughly 24 billion, according to Roku, up about 61 percent from 2017.

Roku also reported 27 million active accounts in its fourth quarter, up about 40 percent year-over-year. This tracks closely with analyst predictions of 27.1 million active accounts, according to FactSet estimates.

The stock ended trading at $42.18 per share Monday afternoon with a market cap of about $4.5 billion.

Roku offers streaming players and TV models that let customers stream content from various services through their devices, offering consumers a simple way to watch video content without a cable or other pay-TV subscription. Roku competes with other streaming devices like Apple TV, Amazon's Fire TV Stick and Google's Chromecast.

KeyBanc Capital Markets rated the stock as overwieght Monday with a $59 price target, saying the numbers were well above their estimates for Q4 2018. In a note, the analysts also referenced Roku's separate announcement Monday that Westinghouse Electronics will join the Roku's TV licensing program. In a press release, Roku said HD Westinghouse Roku TV models are expected in the first half of 2019, with 4K Westinghouse Roku TV models available later in the year.

"This is notable for a couple reasons. First, it is another proof point that OEMs continue to see value in the Roku operating system and validates the competitive moat," the KeyBanc analysts wrote. "Second, this is an Amazon Fire TV (smart TV) customer, which highlights Roku's strong competitive position, in our view."

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