For the past three years America's outdoor advertising industry has been developing a ratings service that will place the sector on the same level as other mainstream media - especially TV.

Outdoor media owners have been working within Nielsen's Global Outdoor Advisory Committee, a group of advertisers and agencies, to agree, design and evaluate Nielsen Outdoor's new GPS-based ratings service.

This week sees the publication of the service's debut ratings report, which reveals that outdoor - second only to the internet as the fastest-growing US medium - is less cluttered than other popular communications channels, the average adult being exposed to only forty outdoor messages daily.

The nascent service is already up and running in Chicago, beyond whose windy boundaries Nielsen Outdoor's managing director Lorraine Hadfield hopes to expand the ratings service.

Says she: "For the first time in its history, the outdoor advertising industry now has a reliable people-based measurement system that delivers true reach, frequency and ratings data, complete with audience numbers and demographic breaks."

Data sourced from AdWeek (USA); additional content by WARC staff