(CNN Money) — Netflix shares sank about 13% after hours when the streaming service reported subscriber numbers that were lower than expected.

The company added 5.2 million subscribers in its second quarter, about 1 million less than what its own forecast showed. It now has about 130 million worldwide.

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In a letter to shareholders, Netflix said it had a “a strong but not stellar” second quarter.

The company’s earnings beat Wall Street’s forecast, but sales were below targets.

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Netflix in its letter to shareholders acknowledged that it expects to face more competition going forward, including from AT&T, which now owns HBO, Warner Bros. and CNN.

Disney is also planning its own streaming service, which is expected to launch in 2019. It is close to finalizing a deal for the movie studio assets of 21st Century Fox. Disney would also inherit Fox’s share of Hulu if that deal goes through, giving it a majority stake in that streaming service.

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