Monitor-Plus will provide Carat with a complete view of advertising information, including local coverage with spot TV measurement and brand level detail for spot radio.
Neither agency could be more specific about the length of the multi-year deal because of legal clauses in the contract.
Kyra Koury, senior vice-president and national sales director for Monitor-Plus agency sales, said: "We are proud to continue and strengthen our relationship with Carat by providing it with competitive spending information."
Carat USA is the latest client to sign for Nielsen Monitor-Plus. Other recent agency wins include Dailey & Associates, Crispin Porter & Bogusky, The Vidal Partnership, Colle+McVoy, Dieste Harmel Partners, and Zubi Advertising.
Nielsen Monitor-Plus already provides ad information to US media agencies including Omnicom agencies, Starcom MediaVest Group, MediaCom and Media Planning Group.
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