• by Erik Sass  @eriksass1, January 12, 2009

CBS Radio's network of radio station Web sites saw its total number of unique visitors increase 30% in December 2008, compared to the same month in 2007, according to Web analytics service OneStat.com, reaching an all-time high for CBS Radio. The online measurement company also noted that unique visitors grew 7% between November and December 2008.

Among the biggest growth stations were KRLD-Dallas, which jumped 133% between December 2007 and 2008; KNX-Los Angeles, up 113%; and WBBM-Chicago, up 104%. Major increases were also seen at WCBS-FM-New York and WPGC-Washington.

As revenues from traditional channels slump, the growth in online radio audiences and ad revenues has been a bright spot for the radio business in general.

According to outside observers, Clear Channel, a CBS Radio rival, will see Web revenues on track to reach $70 million to $80 million by the end of the year. (The company, now privately held, will not release separate figures for online revenues). Evan Harrison, the president of Clear Channel Radio's online division, confirmed that the Web ops posted about 20% year-over-year growth thus far in 2008, adding that August was their biggest revenue month in history.

Still, online revenues remain a small part of the business for most radio broadcasters. In the first three quarters of 2008, the Radio Advertising Bureau's "off-air" category (which includes online revenues) amounted to $1.35 billion, or about 9% of the total $14.83 billion. While it grew 9% from $1.23 billion in the same period in 2007, the increase of $120 million could not offset an overall revenue decline of more than $1 billion.