Nielsen Admits ‘Technical’ Screwup Has Impacted Network TV Ratings Since March

Nielsen has admitted to recently discovering a “technical error” that has impacted national network television ratings over the past several months. It made the find after investigating “recent ratings irregularities.” The error dates back to March 2, 2014, and was “generally imperceptible” before fall premiere week. In the “vast majority” of cases, the impact was minimal, in Nielsen's words. In some cases, however, it was “more significant.” The mistake does not affect cable and local TV ratings.