In terms of radio listening, Nielsen found that 16% of teenagers around the world consider radio their "primary source" of music, with another 21% identifying it as a "secondary source" of music. But the numbers lag far behind MP3 players -- identified by 39% of teenagers as a primary source of music -- and computers, preferred by 33% of teens.

Indeed, the Nielsen study ended up damning radio with faint praise. For example, Nielsen's observation that "teens may find themselves in older cars not yet equipped to play from their MP3 player" hardly inspires confidence, suggesting a residual audience held in place by technical limitations that will eventually be lifted.

Likewise, Nielsen's assertion that "radio still serves as an information source for local social happenings of extra relevance to teens" describes a function that is marginal to radio's overall business, and also an easy target for disintermediation by online media.

In terms of online media behavior, Nielsen found that teens are actually online a great deal less than adults overall -- spending an average of about 11.5 hours per month on the Web versus a national average of 29.25 hours per month. This was attributed to competing time demands for school, work, and recreation, which translate into less consumption of online video as well.

On the other hand, teens are avid consumers of mobile video -- spending 6.5 hours a month watching mobile downloads and streams, versus a national average of about 3.6 hours.

The trend lines for radio's teen and young adult demos are hard to get a handle on. Last year, Arbitron found that 90% of people ages 12-17 still listened to radio at least once a week. The number increased to 93% among adults ages 18-23. In another heartening result, Arbitron found that radio reached 95% of college graduates ages 25-54 every week. Stations affiliated with networks reached 85% of college graduates ages 18-49.

Conversely, the average amount of time spent listening to the radio is down significantly, dropping 5% from 19 hours and 32 minutes in 2007 to 18 hours and 30 minutes in 2008. The decline in average time spent listening is partly a result of the growing popularity of MP3 players and iPods, as well as non-radio audio delivered via the Internet.

In June 2008, Coleman Insights found that daily radio listening by teenagers was on the downswing, losing share to the new media options. Specifically, Coleman found that 84% of the 14-17 cohort listen to music daily on an MP3 player, iPod or computer, versus 78% for radio. A second Coleman study found that the 15-17 cohort favors iPods and MP3 players as primary destinations for listening to music -- with 41% choosing the personal devices, compared to just 22% for FM radio.

Also, Edison Media Research found that college graduates ages 25-54 listen to radio significantly less than their counterparts without college degrees.

Based on Arbitron's paper diary ratings from spring 2007, Edison found that weekly listening among the 25-54, non-college grads was 21 hours and 15 minutes; for college grads, it was just 15 hours and 45 minutes -- a difference of five-and-a-half hours, or 26% less than the non-college total.

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