In case you don’t know, the gross rating point (GRP) is a measure of the reach of a campaign and how often people saw it.

For example, a campaign reaching 12% of the total population with an average frequency of three exposures has 36 GRPs (12×3).

GRPs have been the standard measure for TV audiences for decades – particularly in the US – being well suited to the sheer scale of linear TV viewing. They also provide nice simple planning assumptions:


That is, if you want to reach more people you simply have to spend more. If you want to hold spend constant but still reach more people then you either need to reach them less often or buy lower-priced media. 

This simplicity has allowed brands to deploy significant budgets against TV for decades. If you deploy significant budget it shows up in econometric models and it then becomes possible to demonstrate ROI and, therefore, justify spend.

Consequently, due to the natural inertia of industries, it’s easy to see why planners also want such a simple measure for online video that:

  1. De-duplicates the increasingly fragmented way people watch content and ads today.

  2. Provides simple assumptions about changing spend.

However, a single metric for online video comes at a price. You can’t differentiate between the unique methods of engagement and receptivity to advertising on different devices, content types and contexts.

Also, online advertising rarely has the weight of familiar econometric models behind it to meet the second element. 

GRPs are also useful for a third reason. They come bundled with audience demographics, a very familiar metric (known as targeted rating points) allowing brands to understand and buy a specific target audience. 

Consequently, online video has bent over backwards to harness a metric that makes it easier for TV advertisers to understand and spend online.

But herein lies the fundamental problem in transposing a TV metric to an online environment. It misses the vital point that what a consumer is interested in is more important than their demographic.

I’ll use a surfing anecdote to explain (the water not online variety). A surfboard manufacturer assumes it should target males 18-25 because that’s who they sponsor and that’s who turn up at their events.

However, if you ever go surfing you find it’s everyone else too. So, planning only to 18-25 males, the surfboard manufacturer would miss all these other groups.

Instead, they should plan to all people interested in surfing. For scale, they could expand to those interested in water sports, then those living within driving distance of surf areas, then those going on holiday to popular surf destinations.

The GRP was born in a time when TV was viewed on a single household device, when there were relatively few channels, and a limited number of set piece shows and events. Today’s world though is big, noisy, cluttered, and connected.

It’s simply not feasible to treat digital video the same way we treated TV, something UK marketers seem more attuned to.

Although UK marketers are familiar with GRPs, the dominance of TV in the US and the scale of video opportunities being far greater there – such as Hulu, HBO GO and YouTube – means the temptation to plan online video campaigns like linear TV among US marketers is much greater.

But what about attention? In today’s fragmented media consumption world it’s hard enough to get the right video ad, in front of the right person, at the right time for them. At that crucial moment, the question is “what did the brand hope to achieve?” 

In the UK, we think marketers and agencies are increasingly persuaded that focusing on attention metrics like the average time spent forces them to value real people taking a few precious moments with their brand…not just the simplicity of planning to reach and frequency.