In the US DEC (Daily Effective Circulation) has been used for over 20 years to measure how many people have the opportunity to see a billboard. So, if the DEC of a wall in Times Square is 1.5 million, then that is the number of people that could see it on an average day. The vagary of the DEC is probably what has kept OOH to only 4% of the total advertising-spend in the US each year.
The New EOIEOI (Eyes On Impressions) is the industry’s first real attempt to get on par with traditional forms of media. The EOI measures the amount of people likely to see an ad by measuring format and location. The numbers will be measured on a weekly basis as opposed to a daily one. The EOI will be deployed in the top 200 markets, which is so important to giving the measurement a fighting chance for survival.
The first Eyes On test results are set to be released in June 2008, so there isn't much hard data to go on, yet. Additionally, the program is focused on static billboards and other traditional OOH materials, though presumably it could be adapted for use with the changing media on electronic billboards and digital signs. While better and more verifiable measurement can't hurt, to us it seems unlikely that they'll significantly aid the outdoor ad movement either. Granted, it's doing pretty well on its own right now, so there's no reason to predict a decrease in activity. However, at this point it seems like the complexity of planning and buying a large OOH campaign remains the largest challenge for media buyers and brands, not the availability of newer or better metrics.