This form of outdoor advertising provides many unique advantages for advertisers, such as instant creative changes and messaging flexibility, and they can incorporate dynamic content, dayparting, and even social media feeds. Not to mention, advertisers rarely have to worry about production costs since no printed materials are required. However, despite all of the advantages, some advertisers still wonder how many people are actually seeing their ad when they drive by a digital billboard.  After all, it’s not shown on the board 100% of the time as it is with a static board. On a typical digital billboard, about six to eight advertisers are rotated through. How many digital ads does a driver actually see when they drive by? And more importantly, how many people will see your digital ad?

Earlier this summer, the Traffic Audit Bureau (TAB) announced advancements in their measurements of billboard impressions, which will provide more accurate impression numbers for their audited digital inventory (about 4,000 digital structures nationally) and will provide more clarity on how many people see each digital advertisement, versus each digital structure. The advancements will also affect measured impressions for their audited static billboards as well. In order to better understand the new advancements, it’s important to first note how out-of-home measurements have evolved in the past couple of years. For a long time, billboard impressions were calculated using traffic counts only, based on an estimated number of vehicles traveling on a particular road. In 2010, a new ratings system was implemented which provided much more accurate impression numbers for each billboard structure. These were calculated using additional variables, such as board size, distance from the road, readability, and the angle of the billboard. The new system also incorporated demographic information, thereby allowing out-of-home to be measured comparably to other media types such as TV and radio.

Although the new measurement system in 2010 was well suited for static billboards, questions still remained around digital billboards since multiple ads were being shown on these structures. For digital billboards, measured impressions were provided for the structure as a whole and did not break out impressions for individual advertisements. This left advertisers applying an adjustment factor to account for their portion of the rotation. TAB’s recent advancements will now help answer these questions, since the measurements will include new variables such as traffic speed, congestion, and road type. It also takes into account how far away a driver is when they first see a billboard – when speed is factored in, TAB can then determine how many digital ads the driver will potentially see. Since the new measurements have been implemented, TAB has seen more accurate impression counts not only for digital billboard ads, but for static billboard ads as well. The congestion factor has certainly helped ratings, as billboards located on busier, more congested roads will undoubtedly see increased impressions. Conversely, billboards located on more local roads or on roads with less congestion (i.e. faster speeds) are seeing lower ratings due to the new measurements. Moving forward, TAB will no longer report on impressions for an individual digital billboard structure.  Instead, ratings will be provided on a per spot basis.

It’s important to keep in mind that the results from the recent billboard measurement changes will vary from market to market, depending on its outdoor inventory and traffic patterns. However, the advancements will certainly provide more clarity on how many people are actually seeing your digital billboard ad and will keep outdoor companies more accountable when selling digital ad space.

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