• by Erik Sass  @eriksass1, November 3, 2009

This week brought more good news for radio from Nielsen, which analyzed behavioral data collected by the Council for Research Excellence. In Atlanta, Chicago, Dallas, Philadelphia, and Seattle in 2008, broadcast radio reached 77% of American adults every day, making it second only to television, which garnered 95% daily reach.

The Nielsen data bolsters radio's audience claims at a critical time for the medium -- but it's unclear whether these kinds of findings can still sway advertisers.

Within the audio category, radio's daily reach far exceeded the percentage of American adults who listen to CDs or tapes -- at 37% -- or listen to portable audio devices like iPods or MP3 players, at 12%.

What's more, Nielsen found that the 12% who listen to iPods or MP3 players every day overlap a great deal with the 77% who listen to radio, with radio reaching 88% of the iPod/MP3 group. Compared to other media, on a daily basis radio also beat the Internet -- excluding email usage -- at 64%, newspapers at 35%, and magazines at 27%.

Radio scored even better in the coveted 18-34 age group, reaching about 80% of this cohort on a daily basis.

This is the latest round of positive findings for radio released by Nielsen, which may be trying to curry favor with radio broadcasters as it promotes its new radio ratings service in mid-sized markets.

In September, Nielsen publicized the results of a March and April survey of 119,000 consumers, representing 14 million people in 51 markets across the country -- which found that adults ages 18-34 listen to radio for an average 21.5 hours per week, on par with the rest of the adult population. Even better, the young, tech-savvy consumers that dominate its cell phone-only sample -- 15% of the total sample -- actually listen to radio more than average, clocking 23 hours per week.

Other Nielsen findings haven't been so upbeat, however.

In June, the research firm released a study of teenage audiences, which found that just 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.

In any event, audience size may not be radio's main problem. Over the last decade, Arbitron -- the dominant radio ratings firm -- published a series of surveys which consistently found that radio reaches over 90% of American adults per week, continuing up to the present.

But beginning in the second quarter of 2007, radio revenues have dropped just as consistently for 10 straight quarters (counting the current quarter). While some of this is clearly the result of the broader economic downturn, it may also be due to competition from the Internet, which many advertisers perceive as a more measurable medium -- making metrics, rather than reach, the real issue.