Weekday Audience for Online Radio Networks Grew by 38% between June 2005 and 2006; Midday Cumulative Audience Exceeds 3 Million Listeners

Business Wire, Sept 20, 2006

NEW YORK -- Arbitron Inc. (NYSE: ARB) and comScore Media Metrix, a division of comScore Networks, Inc., released today the online radio ratings for June 2006 whose findings observed a sharp increase in Average Quarter-Hour audience compared to the same month last year.

The weekday Average Quarter-Hour (AQH) audience for the measured online radio networks for June 2006 is 1,031,368 people age 12 and older listening Monday-Friday 6AM-7PM.

The June 2006 audience to the five networks that were measured in the June 2005 report increased 38 percent, growing from an AQH audience of 743,500 in 2005 to an AQH audience of 1,022,400 persons age 12 and older in June 2006. Average Quarter-Hour audiences are the estimated average number of people who listen during any given 15-minute period within a specified daypart.

More than six million different people, age 12 and older, tuned to the online radio networks measured by comScore Arbitron during an average week in June, Monday to Sunday from 6AM-Midnight. The midday cumulative audience (Mon-Fri 10AM-3PM) for the six measured networks in June 2006 reached 3,279,400 listeners.

The June report of the comScore Arbitron Online Radio Ratings service rated America Online's AOL(R) Radio Network; Yahoo!(R) Music; Microsoft's MSN Radio and WindowsMedia.com; Live365; ESPN Radio; and Clear Channel Online Music and Radio during an average broadcast week in the month of June. Ronning Lipset Radio represents all the networks, with the exception of ESPN Radio.

Persons 12 
                        Average Weekly Audience
                               JUNE 2006
                 Geography: United States (50 States)
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                     Monday-Friday 6AM-7PM  Monday-Sunday 6AM-Midnight
                     -------------------------------------------------
                                Average                   Average
                      Cume     Quarter-Hour    Cume      Quarter-Hour
                     Persons     Persons      Persons      Persons
----------------------------------------------------------------------
America Online's AOL
Radio Network        1,106,100      313,700    1,648,200      195,100
----------------------------------------------------------------------
Clear Channel Online
Music and Radio        783,500      130,100      906,600       72,700
----------------------------------------------------------------------
ESPN Radio             124,000        9,000      186,400        5,000
----------------------------------------------------------------------
Live365                515,800      105,900      717,200       60,600
----------------------------------------------------------------------
Microsoft's MSN Radio
and WindowsMedia.com   617,700      153,900      825,900       86,000
----------------------------------------------------------------------
Yahoo
Music/LAUNCHcast     1,505,200      318,800    2,329,300      196,300
----------------------------------------------------------------------
TOTAL: All Six
Networks             4,415,135    1,031,368    6,295,229      615,717
----------------------------------------------------------------------
Total RL Radio
Network              4,297,700    1,022,400    6,116,800      610,700
----------------------------------------------------------------------
Note: Cume is defined as the number of different people who listen
during a given daypart. Cume audience estimates for individual
networks should not be added, because people who listen to more than
one network will be counted twice. The reported audience for the total
of the four networks is an unduplicated estimate of the number of
different people who listened to one or more of the networks for a
minimum of five minutes during the week.
----------------------------------------------------------------------

* ESPN Radio was not part of the measured networks in June 2005. They
have been excluded from the comparison which shows an increase in AQH
audience of 38 percent.

The comScore Arbitron Online Radio Ratings service is based on a subset of approximately 200,000 U.S. participants within the comScore global consumer panel. Using proprietary and patent-pending technology, comScore passively and continuously captures the online behavior of these panelists, including online radio listening behavior. Subscribers receive Average Quarter-Hour and Cume audience estimates for 38 demographics and 15 standard broadcast dayparts. Each month, Arbitron will publish the average weekly audience for Persons 12 , Monday-Friday 6AM-7PM and Monday-Sunday 6AM-Midnight on its Web site (www.arbitron.com).

Arbitron represents the comScore Arbitron Online Radio Ratings service. For more information, contact Diane Williams (diane.williams@arbitron.com) or Bill Rose (bill.rose@arbitron.com).

About Arbitron

Arbitron Inc. (NYSE: ARB) is an international media and marketing research firm serving radio broadcasters, cable companies, advertisers, advertising agencies and outdoor advertising companies in the United States, Mexico and Europe. Arbitron's core businesses are measuring network and local market radio audiences across the United States; surveying the retail, media and product patterns of local market consumers; and providing application software used for analyzing media audience and marketing information data. The Company has also developed the Portable People Meter (PPM(SM)), a new technology for media and marketing research.