• by Erik Sass  @eriksass1, February 9, 2011

National radio sales came surging back in 2010, according to Katz Radio Group, a national sales rep firm owned by Clear Channel Radio. This week, President Mark Gray (who assumed the role after longtime Katz boss Stu Olds passed away in December) circulated a memo to employees tallying some of the medium's successes over the last year.

Overall, national spot radio sales were up 17.7% in 2010 compared to 2009, Gray wrote, crediting the growth to increased spending in categories including auto (up 27.4%), telecom (21.3%), retail (18.2%), consumer products (19.9%) and entertainment (9.7%), as well as "an extremely active political season" leading up to the bitterly contested November midterm elections.

The Katz memo confirms earlier trends reported by the Radio Advertising Bureau, which identified national advertising as the top percentage growth area for radio, after digital. In the first nine months of 2010, total national ad sales increased 14% to $1.97 billion, according to the RAB, outpacing local -- long the mainstay of the radio business -- which edged up just 3% to $8.46 billion in the same period.

In dollar terms, that means national ad spending increased by about $242 million in the first nine months of 2010, per the RAB, compared to a $246 million increase for local ad spending.

However, the strong performance in 2010 makes for tougher comparisons in 2011.

Gray noted that a number of factors have constrained national ad sales growth in the first quarter of the year, including "unprecedented weather disruptions in major media markets." As a result, current pacing data suggests that national spot radio will be flat in the first quarter compared to the same period last year.