"After analyzing the study of 30-second ratings, the general consensus of our clients is that additional sub-level studies are not needed at this time," said Nielsen CEO Susan Whiting, in an advisory sent to clients on Thursday. Whiting indicated that Nielsen is still open to conducting custom research studies of shorter ratings intervals, adding, "We are, of course, willing to assist in whatever additional research our clients require in this area," but said the industry standard data provided to national ratings clients and the third-party processors they use would be based on the minute-by-minute data files Nielsen also began providing on Thursday.

While the minute-by-minute data does not necessarily coincide with the exact times that TV commercials air, advertisers and agencies believe it is at least close enough to actual commercial ratings to serve their needs for now.

"This push to gain granular visibility and understanding of commercial vs. program ratings is critical for the accuracy of media measurement in the U.S.," said Bob Liodice, president-CEO of the Association of National Advertisers in a statement issued by Nielsen. He added that the new ratings represent "a significant step in the right direction."

On Monday, Bruce Goerlich, executive vice president-director of strategic resources at ZenithOptimedia USA, told attendees at a Radio TV Research Council luncheon in New York, that minute-by-minute ratings were an important breakthrough for marketers and agencies, and would get the industry closer to a true measure of "engagement," a new metric being bandied as the industry's new standard.

While the minute-by-minute data won't provide actual TV commercial ratings, Nielsen said the weekly files would identify which minutes commercials actually air in.

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