New York - Mar 12, 2002 - Arbitron will begin using its radio diary database to increase the sample size used to tabulate the audience estimates for the its RADAR network radio ratings service beginning with the release of the RADAR 73 network radio ratings report in June 2002.

RADAR, an acronym for Radio's All Dimension Audience Research, is a national radio ratings service that measures audiences to radio commercials aired on 31 radio networks operated by ABC Radio Networks, American Urban Radio Networks, Premiere Radio Networks and Westwood One Radio Networks. Arbitron acquired the RADAR radio network ratings service from Statistical Research, Inc. in July 2001.

The service currently produces its estimates using a 12-month, 12,000-person telephone survey in combination with the industry-standard commercial clearance collection system. Beginning with the release of the RADAR 73 report in June of 2002, Arbitron will use 12,500 diaries in each of the most current quarterly periods of the 12-month RADAR survey and will drop 3000 telephone interviews from each of the earliest quarterly periods of the previous 12-month RADAR survey. By the release of RADAR 76 in March 2003, RADAR reports will be based on an annual sample of 50,000 radio diaries - more than four times the current sample.