Ad Retention Index

July 21, 2012

See Also: Commercial Viewership Index

CIMM DEFINITION: The ratio of commercial viewing average audience to total program viewing average audience. (Source: Rentrak)

NOTE – This is not recommended as a general industry term because this ratio is reflective of not just pure ad retention but also the program audience trend from beginning to end may be increasing or decreasing as at the beginning or end of prime time. TRA for that reason calls this the Commercial Rating index (CRI) – the index to the average program rating – which is what is clearly is. Ad retention should be measured against the base of homes that start the commercial. (Source: TRA)