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The wireless business contributes nearly 70% of AT&T's revenue. The firm is the third-largest US wireless carrier, connecting 72 million postpaid and 17 million prepaid phone customers. Fixed-line enterprise services, which account for about 15% of revenue, include internet access, private networking, security, voice, and wholesale network capacity. Residential fixed-line services, about 11% of revenue, primarily consist of broadband internet access, serving 14 million customers. AT&T also has a sizable presence in Mexico, with 23 million customers, but this business only accounts for 4% of revenue. The firm recently agreed to sell its 70% equity stake in satellite television provider DirecTV to its partner, private equity firm TPG.