New York-Due to a software glitch, Nielsen Media Research miscalculated distribution numbers for individual cable networks in May, causing a delay in the release of cable ratings last week.
Nielsen sent out a notice to its clients last Wednesday warning them about the "data anomalies." The news forced some cable programmers to retract or delay issuing press releases on their May ratings, which had been calculated using the faulty subscriber data. Those ratings had to be redone by Nielsen using the new, revised subscriber numbers.
Nielsen released its corrected subscriber numbers last Thursday, but as of press time last Friday it had not issued revised cable ratings.
Of the 50 networks that Nielsen tracks, subscriber counts for 43 had errors of less than one-half of 1 percent, according to a Nielsen spokeswoman. The errors for five other cable networks-Fox News Channel, Game Show Network, The Golf Channel, The Movie Channel and Travel Channel-ranged from 0.5 percent to 1 percent.
Lastly, the percent errors for two networks-Great American Country and Animal Planet-were more than 1 percent. Nielsen originally put Animal Planet's distribution at 60.75 million subscribers in May. The revised Nielsen number was 60 million, a difference of 715,000 subscribers, or 1.18 percent. The percent error for GAC was 1.29 percent, with its revised May numbers dipping slightly to 14.9 million from 15.1 million.
A Discovery Communications Inc. spokeswoman said the company wouldn't know how the change in the distribution number would affect the ratings for Animal Planet, or any other Discovery networks, until this week.
Nielsen learned about the problem with its software when it was checking its cable-network "coverage-area universe estimates" for June-the estimates of how many subscribers a service has.
"Upon further research, we discovered that the software problem was first introduced last month and, accordingly, all cable-network coverage-area universe estimates for May 2000 already released by NHI [Nielsen Homevideo Index] are incorrect," Nielsen said in its memo to clients.
Because of the Nielsen software problem, Turner Broadcasting System Inc.-which acts as a source of basic-cable ratings for the media-was forced to delay releasing its May ratings information for overall cable, as well as for individual cable networks.
Turner had issued some preliminary May sweep and 1999-2000 ratings data from Nielsen before the Memorial Day weekend based on the incorrect subscriber numbers. Turner had been set to release final numbers for basic cable and individual networks last Wednesday, but it couldn't because of the Nielsen snafu.
A story on preliminary May ratings in this week's issue (page 30) went to press before Nielsen released its alert.
Lifetime Television-which issued a press release on May ratings last Wednesday, before getting the warning memo from Nielsen-had a spokeswoman call reporters to ask them not to use those numbers.
As it turned out, the Lifetime spokeswoman said, the error on the network's subscriber numbers was so small, at 0.01 percent, that the initial May ratings number was unchanged.