Can we measure how many people see poster campaigns?
Andrew GreenZenithOptimedia
BACKGROUND
Advertisers spent $23.8 billion on outdoor worldwide in 2006, representing 5.6% of total spending on mass media.1 It is one of the least well-researched media, with many countries having next to no comprehensive estimates of poster audiences.
Even where audience data have been produced, media planners have been sceptical of the large numbers generated. It used to be a rule of thumb in the UK market, for example, that 1,000 large roadside panels would reach 85% of an audience an average of 25 times. In...