We know that posters are great at reaching lots of people quickly as well as building cost-effective frequency. They are unavoidable in our everyday lives and we see many different formats in different environments at different times of the day. This versatility means billboards have great potential for building brands, but can posters sell product?
In 2005, TNS was commissioned by the outdoor industry to design a project which would provide evidence that posters can change the purchase behaviour of consumers. Using Superpanel*, this single source database allows us to look at both media consumption and purchasing behaviour information from the same set of people. Therefore we can determine who was most likely to see the advertising and then find out whether they went on to buy the advertised brand. The study used nine brands from various sectors with a variety of outdoor formats.
The survey sample was divided into two groups of respondents: those who had been heavily exposed to outdoor advertising and those who were considered to be light viewers of the medium. If Outdoor affects sales, we would expect to see a small uplift among light consumers of Outdoor but a far greater sales uplift among the heavily exposed group.
We established a base by tracking average sales across a period prior to the poster advertising, against which we could then compare the average sales across the period of the poster activity amongst the two groups.
So what did our research show? An aggregate of the results across all 9 brands showed increases across both groups of respondents across the period of poster activity. The average value share for the light exposure group increased from 13.8% to 15.1% - an increase of 9.5%. However, the heavily exposed group increased its share from 12.1% to 14.4% during the poster activity - a 19% rise in share. The key difference between the two groups was their exposure to posters, which suggests that this extra 9% increase in value share is being created by the posters.
Further examination of some of the individual results allows us to develop a bit more understanding of Outdoor’s role in shifting sales of the brand.
Diet Coke with Lemon used roadside billboards as a solus medium. The results were startling. We found that those heavily exposed to Outdoor showed a 26% increase in value share compared to 4% amongst those lightly exposed. This indicates that the group who are more likely to have seen the Diet Coke with Lemon advertising went out and bought the brand as a result. Whereas the group who were less likely to have seen the advertising did not significantly change their purchasing behaviour.
Danone Actimel used Outdoor alongside TV to promote the brand. To study this mixed media effect, we amended our media group definitions slightly. This time, we divided the panel into 3 groups taking into account their level of exposure to both TV and Outdoor.
• Light consumers of both Outdoor and commercial TV
• Heavy Outdoor consumers but light TV viewers
• Those heavily exposed to both
The first group showed an increase in sales of 7.1%. The group who were heavily exposed to the Outdoor campaign, but didn’t see much TV advertising, showed a sales increase of 15.9%, demonstrating that Outdoor has been a key medium driving the effect. Finally, the group who were heavily exposed to both Outdoor and TV responded best, with a 19.1% increase, showing that the mediums work well together.
So, are posters just a showcase for big brand campaigns or do they offer more tangible value to advertisers and their agencies? We think it is the latter. Our research shows that posters CAN deliver against the ultimate key effectiveness metric – sales. It also proves that they can do this either as a solus medium or as part of a mixed media campaign. A step forward for Outdoor and hopefully for planners and their clients too.
* TNS Superpanel: 15,000 households in GB continuously record their purchasing of all products carrying a barcode, whether that purchase has come from their main weekly supermarket shopping trip, or from popping round to the local garage for a pint of milk and a loaf of bread. Anything which is taken back into the home will be recorded. This information is pulled together and reported every four weeks. As it’s a continuous panel, behaviour may be measured over time, meaning that behavioural change may be examined. Additionally, a questionnaire is sent to the main shopper every six months telling us about their media consumption habits. They are asked which media they use, across television, print, radio, cinema, the internet, and outdoor. About 80% of our panellists respond.