Nielsen’s undercount of out-of-home TV viewing disclosed late last year was much worse than the measurement giant initially indicated and disproportionately missed young, Black and Hispanic viewers, according to a report released today by the Video Advertising Bureau.

The VAB said Nielsen’s recount so far shows $350 million in lost network revenue and suggests the overall total will be more than $700 million.

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"We reviewed the information shared by the VAB today, and while we acknowledge the understatement in a portion of our national out-of-home audiences, we stand by our prior statements that the magnitude of the issue was very small for the majority of telecasts," a Nielsen spokesperson said via email. 

In a bad news dump during a holiday week, Nielsen reported on Dec. 22 that out-of-home viewing hadn’t been reported for broadband-only homes in national audience measurements from September 2020 through December 2021.

Nielsen has since reprocessed half of the 16 months in question, according to the VAB, and the results show a far bigger impact than previously disclosed.

Overall, the reprocessed months so far indicate a loss of $350 million in ad revenue for networks, according to the VAB, and since those months represent less than half the total undercount period, the group estimates the total impact at more than $700 million.

The undercount resulted in 30 billion ad impressions disappearing from May through December 2021, including 10.5 billion among people 18-34. Of those 30 billion lost impressions, a disproportionate 7 billion were ads seen by Black viewers, and 5.5 billion were seen by Hispanic viewers. Black and Hispanic people made up close to 42% of the lost impressions, compared to making up 31% of the overall U.S. population in the 2020 Census.

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The undercount comes at a time when Nielsen is trying to win back support from media companies, agencies and marketers to regain accreditation from the industry’s Media Rating Council, which was suspended in September over other undercounting problems.

It also comes as Nielsen is beginning to open an early version of its next generation Nielsen One cross-platform measurement platform, which is ultimately expected to replace its current TV ratings.

The VAB in its report said the errors are “cause for concern about Nielsen’s core competency, and their ability to implement complicated cross-platform products using that same foundation.”