Financial news network CNBC will no longer rely on TV ratings specialist Nielsen to measure its daytime audience, beginning later this year. Instead, it has retained marketing and research firm Cogent Reports for the task.

For years CNBC and its parent company, Comcast Corp.’s NBCUniversal, have complained that Nielsen underreports the size and wealth of its audience by failing to track “out of home” viewing in places such as offices and airports.

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