This collective decision, revealed by RAB President Jeff Haley in an interview with Radio & Records earlier this week, follows last week's announcement by CBS Radio that it would begin posting ratings. (at the time CBS did not indicate the move was part of an industry-wide plan).

Participating broadcasters also include Clear Channel Radio--whose CEO John Hogan is said to have pioneered the initiative--as well as Citadel, Cumulus, Greater Media, and Entercom. Haley is expected to formally announce the plan on May 11, with a vote by RAB members scheduled for the May 21 board meeting.

Posting ratings is already common in television, but less so in radio, where many broadcasters publicize them only selectively. Posting the figures makes it easier for advertisers and media buyers to do quick comparisons over time and between broadcasters.

Ratings also give media buyers ammunition for demanding makegoods or other compensation when a particular program fails to deliver the promised audience numbers.

Media buyers have long asked for speedier delivery of radio ratings and more accountability from broadcasters in delivering promised audience sizes. In November 2007, for example, MindShare said it will begin requiring audience-size guarantees, based on Arbitron PPM data, when it buys ad inventory in Houston. Those broadcasters that fail to achieve 90% of the target audience size, per PPM, will be required to make up the difference with extra ad inventory.