Despite having experienced a slight decline in demand during the coronavirus pandemic, out-of-home (OOH) media has largely blossomed over the course of the last two years or more.

This is borne out by the numbers, with the total OOH marketplace growing by a whopping 9.4% year-on-year during the second quarter of 2019. During this time, the market’s yield increased from £284 million to £310 million, with this trend expected to continue in the wake of the coronavirus outbreak.

It has also become increasingly easy to measure the efficacy of OOH campaigns in recent times, thanks to technological advancement and the rise of integrated marketing campaigns. But how exactly is OOH measured, and how can you accurately gauge the impact of particular campaigns?

Getting Started – Measuring Your Audience

OOH has always been a unique advertising medium, with this status having been reinforced by the rush to digital advertising channels.

However, OOH is also unique in that it’s capable of providing accurate measurements that are based on viewed impressions. This contrasts sharply with most other media, which produces metrics on the basis of the estimated number of people who could have interacted with a particular advert.

In this respect, OOH measurement is underpinned by the so-called ‘opportunity to contact’ (OTC) principle, which is essentially a metric that estimates how many people will walk past your advert and see its content. 

To help achieve this objective, this metric will factor in both survey data and mobility modelling, and it’s fair to surmise that accurate measurements and estimations rely on information being drawn from a number of different sources.

In the case of mobility modelling, this draws data from a detailed global travel survey, which is actually based on a representative population and helps to identify patterns pertaining to the movement of your target audience.

Historically, these surveys were almost always based on memory, but they’re becoming increasingly detail-oriented and capable of drawing information in real-time. 

More specifically, real-time consumer mobility data can now be recorded and shared in real-time, largely through mobile devices and the measurement of detailed GPS and Wi-Fi signals. 

With the increased sophistication and exponential growth of smartphone technology (mobile penetration rates are now in excess of 90% for most demographics in the UK), modern travel surveys can even incorporate accelerometers, barometres and compasses to establish the modes of transport used by target consumers and the precise outlets that they visit.

Of course, the motorists amongst you will often notice 48 or 96-sheet billboards positioned at roadsides and along busy commuter routes, with this type of advert ideal in a society where 36% of the UK population continue to drive to and from work on a daily basis.

So, another key OOH measurement tool is provided by vehicular data, which incorporates wider travel survey information with big data sets of traffic flows from targeted geographical regions.

This broad data set is extremely beneficial for OOH marketers, as it can help to collate information on every conceivable mode of traffic and simultaneously draw statistics from several different sources.

These include official government traffic counts, transport authority data and GPS signals, while the continued integration of real-time sensors on ad panels is also helping to create a deeper level of insight and deliver more accurate information.

As an extension of this technology, digital billboards are increasingly using in-built sensors and cameras to observe consumer behaviour and measure engagement in real-time.

Interestingly, this practice has come under fire in some instances, with the Dutch Data Protection Authority AP in the Netherlands introducing a regulation that compels advertisers to secure permission from passing customers to ensure compliance with current GDPR laws.

Regardless, there’s little doubt that this technology is here to stay in the UK, as advertisers look to increase the accuracy and efficacy of their OOH measurement techniques and access more detailed insights in the process.

Measuring the Effectiveness of Your Campaigns

While the techniques referenced above will help you to accurately gauge impressions and the reach of your OOH or billboard ad, this means little unless you can determine whether or not this helped you to achieve your core marketing objectives.

Whether you’re striving to build brand awareness and recognition or simply want to optimise sales of a particular product or range, it’s important to engage the effectiveness of your OOH campaign and its impact on the actions of consumers.

Arguably, the easiest and most basic way to measure the effectiveness of OOH media is to monitor sales, ideally before, during and after the campaign. You should also combine this information with average sales figures over an extended period of time, before identifying any spikes in sales and the most likely causes for this.

Hopefully, you’ll be able to see a direct correlation between increased sales and your OOH campaign, even though alternative factors may have also influenced this trend.

There can also be no doubt that this metric is easier to measure when operating integrated marketing campaigns, as this enables you to link the timing of any sales spikes to specific stages in the typical consumer journey. If sales have spiked after customers have been exposed to your billboard or OOH ad, you can rest assured that your campaign has ultimately proved effective.

If you don’t run integrated campaigns but want to accurately measure the effectiveness of each one, we’d definitely recommend scheduling these separately and monitoring results on a daily basis.

If you’re willing to engage with more involved techniques for measuring effectiveness, you could consider creating ad-specific coupon codes and vouchers. 

The same principle can apply to using campaign-specific URLs and QR codes, so long as they’re exclusive to your OOH media and available within a limited context.

Recent studies have also shown that OOH media is now considered to be a prolific driver of online activations and brand searches, particularly online and through social media channels such as Instagram.

In fact, OOH generates a whopping 26% of the gross search activations initiated by all offline media in the US, despite accounting for a paltry 7% of the total advertising spend in this region.

As a result of this, there’s a clear opportunity to use dedicated slogans and primary messaging across your OOH ads, which are likely to trigger subsequent relevant keyword searches online. The number of related searches can be easily tracked and measured online, creating another way of gauging impact and influence.

What are the Best Ways of Measuring Your OOH Campaign?

At this stage, you should have a broad understanding of the key metrics that can be used to measure the reach and effectiveness of your OOH campaign.

But what does all of this mean in practical terms? Below, we’ve looked at some corporeal examples and steps that you can take to actively measure your OOH campaigns. These include:

Create a Dedicated Landing Page or Microsite

In addition to creating a dedicated slogan for your OOH ad campaign, you should consider directing online traffic to a microsite that’s specific to your advert and messaging.

This works particularly well if you’re launching a new product and wish to advertise this exclusively through your OOH campaign, while best practice should also encourage you to display the microsite’s URL clearly on the billboard or poster.

From here, you can leverage Google Analytics to measure the number of people who visited the microsite directly online, with this capable of providing an incredibly accurate gauge regarding the effectiveness and reach of your message.

When using this marketing technique, you should also link the microsite to your main website and sales portal, as this creates an opportunity for cross-selling without compromising on your ability to measure the campaign.

Track Your Promo Codes

Let’s say that you want to sell a brand new product at a discounted rate, with this promotion available solely through your OOH campaign and for a limited period of time.

In simple terms, you need to create a unique promo code for your OOH campaign or an individual billboard, ensuring that this cannot be accessed through any other channel.

Ideally, customers should be directed to your site and purchase the promoted product using the dedicated promo code, with this providing a quick and simple way of determining how many sales were driven by your campaign.

The execution of this technique is also important, especially in terms of how you articulate the offer. Most importantly, you’ll need to use concise messaging and minimise the amount of text used on your billboard, while promoting the extent of the discount and the requisite promo code. 

Consider the Merits of Social Media and Hashtags

We’ve already touched on the growing link between OOH and social media marketing, with the former increasingly likely to drive activations through sites such as Twitter and Instagram in particular.

With this in mind, one of the best ways of measuring billboard or OOH effectiveness is to create a unique hashtag to engage potential customers offline.

Make no mistake, hashtags have become increasingly prominent in the field of social media marketing, while there are also numerous tools that help you to understand which hashtags are most likely to resonate with your audience.

By heavily promoting your hashtag through your ad, you’ll have an accurate and insightful way of measuring any social media engagement that follows the publication of your ad. 

Social media channels also enable you to understand more about the individuals who are searching for your brand online, and this can deliver far greater insights going forward.

The Last Word

As we can see, it has never been easier to measure the effectiveness of your OOH campaigns, with innovation and the emergence of integrated marketing campaigns helping this drive enormously.

In fact, there are numerous ways through which you can measure both the impressions generated by an OOH ad and its subsequent impact on sales, so the key is to select those that are most relevant to your budget, content and core marketing objectives.

Remember, execution is also key here, so be sure to keep your messaging concise and to the point when designing billboard ads!