Netflix (NFLX) added 7.4 million subscribers in the first three months of 2018, up 50% from the same quarter a year earlier, the company reported on Monday. It now has 125 million subscribers.

The vast majority of the new subscribers, nearly 5.5 million, came from outside the United States as Netflix continues to gain ground in international markets.

The strong subscriber growth came in well ahead of Wall Street's estimates, helping send Netflix stock up 6% in after-hours trading Monday.

Daniel Ives, an analyst with GBH Insights, called Netflix's earnings results “eye popping” in an investor note.

“It shows the company's aggressive international expansion strategy is bearing fruit and putting major fuel in the company's growth engine for the rest of 2018 and beyond,” Ives wrote.

Expectations were high heading into Netflix's earnings report. While several leading tech companies have stumbled this year amid regulatory concerns, Netflix stock has soared 60% on optimism for its original content strategy.

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