There is a persistent myth in the advertising world that out-of-home (OOH) advertising campaigns can’t be measured beyond basic metrics. In actuality, as far as accurate performance measurements go, OOH is as measurable as its digital marketing counterparts.

Advanced planning, tracking, and measurement tools allow OOH advertisers to track and isolate individual OOH inventory units, directly attribute online and offline conversions, and accurately measure return on investment (ROI). And today, OOH advertisers can monitor and make on-the-spot adjustments to optimize their outdoor ad campaigns in real time.

With advertising departments facing increasing scrutiny over their marketing budgets, it’s crucial they have the data to back their decisions. Digital may have been the wave of the recent past, but it’s growing increasingly more expensive while results are decreasing. If you are looking to broaden your media mix to increase brand awareness and drive consumer action, it’s time to give OOH a deeper look. Decisions across your entire media mix come down to performance. Here’s an in-depth look at how you can gauge the performance of your next OOH campaign.

Measurement Methodologies

OOH is a performance channel like never before. With the right OOH media-buying partner, you can understand: Did our OOH advertising campaign succeed? Did more people act than if we hadn’t run the campaign? Did our campaign work and to what degree? Which components of our campaign worked the best?

Advertisers generally turn to two high-level categories of analysis to measure campaign performance: lift and attribution. Lift analysis uses experimentation to isolate the impact of your OOH campaign on business outcomes, and it can be used to measure a specific marketing channel’s success compared to other channels in an advertiser’s media mix. Digging even deeper, attribution analysis examines the components of OOH campaigns to determine the individual ad units that are performing the best, giving advertisers insights they can use to optimize ad campaigns.

These two approaches complement one another and can be used simultaneously. Attribution is best for day-to-day, always-on measurement, while many run lift analyses more sporadically –– after initial experimentation to prove that the OOH medium works.

Metrics to Consider

Alongside how you measure, you also need to consider what you measure.

These approaches to measuring an outdoor campaign’s performance rely heavily on a variety of different metrics which include:

  • Impressions: This is the number of times consumers view an advertisement. In the OOH industry, impressions are measured by considering the amount of traffic that passes by a particular ad unit and the results of eye-tracking experiments which reveal the percentage of drivers that actually view the ad unit. Today, most outdoor advertising companies rely on the non-profit organization Geopath for all OOH impressions data. Geopath’s mission is to independently audit and report OOH advertising ratings throughout the United States.
  • Reach & Frequency: Reach and frequency are commonly used metrics across almost all media channels. Reach is the number of unique persons in a particular market who are exposed to an OOH ad unit at least once over a specified period of time. Frequency is the number of times the individuals reached are exposed to the OOH ad unit during the same time period.
  • Gross Rating Points (GRPs): GRPs are a standard advertising measurement used to track exposure within a specific geographic market. They represent the total number of in-market impressions delivered by an OOH campaign expressed as a percentage of a market population. For example, one rating point or GRP signifies that you’ve reached 1% of the market population. GRPs are calculated by taking the percent of the market reached multiplied by the frequency.
  • Target Rating Points (TRPs): TRPs are essentially just a refinement of GRPs, which only consider your target audience. For example, one TRP signifies that you’ve reached 1% of your target audience within the market population. TRPs are a quick measure of how many people in a target audience an OOH ad or campaign reached and how many times.
  • Outcomes: This is really a category of metrics, but it’s among the most important, because it’s directly related to your unique business goals. When identifying the specific outcomes to measure, first consider what you are trying to achieve. Is it making an in-store, e-commerce, or mobile-commerce sale? Is it seeing consumers visit a physical location? Is it website traffic? Or are you trying to drive consumers to interact with your social media accounts and create social buzz?
  • Halo Effect: Unlike the methods listed above, which measure the direct impacts of a campaign, the halo effect measures the indirect impacts (or benefits) OOH has on your other marketing channels. Of course, these indirect measurements can get complicated, but some OOH media buying platforms make it easy –– thanks in part to direct integrations with other platforms.

The rising costs of digital advertising, coupled with the responsibility to be extra diligent with every dollar spent, means the pressure is on advertisers to prove what they’re doing is working. With the ability to measure the real performance of OOH ad campaigns, outdoor advertising shouldn’t be overlooked as a crucial component of your overall media mix. There’s never been a better time to take advantage of OOH’s performance power.