The text below was from an email Tango Multimedia owner, Terry Fetterman, sent to a client when the client inquired about the importance of Gross Rating Points (GRP) when considering TV advertising schedules.

Are GRP numbers important to track?

Short answer…

Track household (HH) GRPs for broadcast.

For cable, make a note of the total # of HHs in plan, plus an average of HH GRPs between the zones used.

Long answer… 

We look at the following for each schedule

  1. HH GRPs
  2. HH impressions
  3. Primary Demo GRPs
  4. Primary Demo impressions
  5. When booking, we also pay attention to pricing per daypart or show, program/channel content, and number of market HHs
  6. With extra time, we like to also look at impression CPM

Many [clients] like to see Reach and Frequency.

As a young TV ad sales guy, I was trained by the cable ad industry. Reach and frequency were core to our sales effort at validating the recommendations we made to clients.  When I shifted over to selling broadcast TV, our focus shifted to reach and “recency”.  GRPs were not super important in a large TV market, and more important in a small TV market.  One thing though that I learned, as an aside, was the idea of “focus”.  Incorporating focus wherever and whenever possible in a media plan – especially when media budgets limited what could be accomplished.

For your records, I would choose HH GRPs to track for broadcast TV – for now.

At some point, we should also track HH impressions – but this may require additional formulas depending on info shared by our media partners.

For cable TV, that is a trickier wicket.  We are using 4 unique local cable ad zones that combine to reach about 34,000 wired homes.  Each zone has a different schedule.  Plus, there are many homes that we are not reaching at all with cable TV.  Perhaps the best thing to do here is an average HH GRP and make note of the number of homes reached.  Focusing on # of HH impressions would make this easier and arguably more relevant.

Why impressions?  It gets us closer to an apples to apples comparison with other media – at least quantitatively.

There is a qualitative question around: is a static display impression equal to a billboard impression, equal to a radio impression, equal to a video impression…

None of this, however, is a proven science, and more like quasi bullshit sales and self-justification science from the TV industry.

All is based on subtle assumptions, theories on reach and frequency (that philosophically differ between broadcast and cable), and projected ratings formed using last year’s estimated actuals of a particular month or quarter multiplied by an algorithm based on how the quarters and months between last year and this month have trended.  This also doesn’t consider whether the GRPs are prime GRPs or anytime throughout the day GRPs – another qualitative consideration.


All that said, tracking based on the same criteria shows us trends and comparative data… plus over time, may provide insight to instore activity.

Let’s track HH GRPs, and at some point commit to including HH impressions.

Gigi Cronin is instrumental in our process of preparing media plans here at Tango. Prior to joining Tango 10 years ago, Gigi was the Director of Research for Comcast in Philadelphia.  Comcast is one of the largest cable operators in the country, and I suppose media-content companies.  Among other things, Gigi taught the Comcast sales staff how to use targeting, research, ratings, reach and frequency to sell and justify ad plans – and to deliver effective schedules.  Later (basically here at Tango) I discovered from Gigi that what she was also doing was protecting Comcast’s profitable use of inventory… lol

Terry Fetterman, Owner of Tango Multimedia