(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.

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.

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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