Whoops. Nielsen, the company that compiles TV ratings, has revealed that a software glitch may have affected TV ratings over several months. From the company’s official statement:
In response to recent ratings irregularities, Nielsen conducted an extensive internal investigation of our systems and processes. On Oct. 6, 2014, we uncovered a technical error that impacts national network television ratings over several months.
The technical error was introduced on March 2, 2014, and was generally imperceptible until we saw high viewing levels associated with fall season premiere week. As a result, small amounts of viewing for some national broadcast networks and syndicators were misattributed. Cable networks and local TV ratings were not affected by this error.
A software fix to correct the problem was deployed on Oct. 9, 2014, meaning that all data being released today and going forward is correct.
Additionally, Nielsen will be reprocessing all previously released data since September 22. It will be reissued by October 17. Also, Nielsen will reprocess all of the impacted data going back to Aug. 18, 2014, when the first new season broadcast network program aired. This data will be reissued by Oct. 31, 2014.
According to The Wrap, it’s ABC network programming that will be most affected.
“Modern Family” and “Scandal” network was getting larger-than-normal boosts in adjusted Live + Same Day viewing numbers
While fast national ratings remained accurate, the final Live + Same Day numbers have been getting slightly erroneous boosts. ABC was the main benefactor of the faux lifts, and thus is the most likely network to see some shows come back down slightly.
That said, it doesn’t sound like any positioning will be changed in terms of overall standings. The insiders we spoke to see shows coming down one-tenth or maybe two-tenths of a ratings point tops, sometimes simply due to new rounding differences.
It appears the impact will ultimately not mean much, or influence network decisions that have been already made. With most network fall premiers out of the way, look for cancellations of poorly performing new shows and announcements of season picks for series that are doing well.