Ad spending among the U.S. media monitored by the Nielsen Co. declined 15.4% during the first half of 2009 vs. the same period in 2008, according to preliminary figures released this morning by the research company. Total spending across those media declined by more than $10.3 billion to $56.9 billion.

Cable TV was the only medium to show significant ad revenue growth, rising 1.5% over the first six months of 2008. Nielsen noted that cable's first-half growth is remarkable, because ad spending on the medium actually declined 2.7% during the first quarter of 2009, indicating that it had an especially strong second quarter.

Except for a 0.6% revenue rise for Spanish-language Cable TV, all other media eroded during the first half of 2009 -- even online display advertising, which declined 1.0%, according to Nielsen's estimates.

Print media experienced the greatest slide. With the exception of local newspapers, which slid only 13.2% during the first half, all other print media eroded at rates of 20% or more during the first half. Local Sunday newspaper supplements had the worst results, declining 45.7%, followed by B-to-B magazines (-31.8%), local newspapers (-22.8%), national Sunday newspaper supplements (-22.4%), and national magazines (-21.2%).

Six of the top 10 product categories reduced spending -- some like automotive (-31.4%) -- significantly. The most significant product category of ad spending gain, direct response (+6.7%), is telling because direct response marketers are typically very opportunistic about advertising rates.

"While some of the larger categories have cut back spending, we see others that continue to raise the ante on their media investments," stated Annie Touliatos, vice president for Nielsen's advertising information services. "What's interesting is that we're not just seeing a rise in spending for recession-friendly products like fast food restaurants. We're seeing a lot more promotion of technological innovations like smartphones, computer software, and consumer-driven Web sites. These advertisers see potential for their products despite our stressed economy and are leveraging advertising to drive their success."