But the TV measurement service added that 98% to 99% of ratings would not be affected by more than .05 of a ratings point.Cable networks and local programming were unaffected.
Recently, some analysts have speculated that ABC’s ratings were apparently given more viewership than other outlets during the opening two weeks of the new 2014-2015 TV season -- especially when it came to increases coming with final live-plus-same-day program rating.
Nielsen executives declined to specify any networks that were affected. Nielsen said the technical error was discovered Oct.6, revealing the erroneous data that stemmed from March 2.
Nielsen has yet to release its first wave of C3 ratings -- the average commercial ratings plus three days of time-shifted viewing data that the majority of TV advertisers used as a measure in guaranteeing their media deals with national TV networks.