• by Wendy Davis  @wendyndavis, October 13, 2006

Yahoo head Terry Semel recently reported that the company last month saw a softness in financial services ads, but that trend doesn't appear to be reflected in the latest numbers from Nielsen//NetRatings AdRelevance.

Financial services companies accounted for 28 percent of online display ads last month--flat from 28 percent in August, but up from 22 percent in September of 2005 and 19 percent two years ago, according to new data from Nielsen//NetRatings AdRelevance.

Yahoo's Semel, speaking at a Goldman Sachs conference in New York last month, warned that the company would fall within the low end of its third-quarter guidance due to a slowdown in growth in financial services and automotive ads.

The Nielsen//NetRatings data reflects only the number of impressions, not pricing--so it's possible that financial services companies and automotive makers have slowed down spending by purchasing cheaper ad units.

Financial services companies were the single largest category of online advertiser, followed by Web media (19 percent of impressions), retail goods and services (15 percent), telecoms (9 percent), and public services (9 percent).

Yahoo's e-mail service accounted for a larger proportion of display ads than any other publisher--42.4 percent--according to Nielsen//NetRatings, but that figure appears to be higher than other estimates. Research company eMarketer recently estimated that Yahoo accounts for a hefty, but far smaller, chunk of the online ad market--18 percent, including search ads. Other popular ad venues, according to Nielsen//NetRatings, included social networking site MySpace, which captured 15.4 percent of display ads, and MSN Hotmail (7.1 percent).

The overall number of cost-per-thousand impression display ads tracked by Nielsen//NetRatings AdRelevance totaled 232.1 billion--down slightly from 233.5 billion in August, but up from 187.2 billion in July, 193.6 billion in June, and 197.7 billion in May. The company doesn't track certain types of online advertising, including pre-roll, partnerships, and sponsorships. The AdRelevance data does not include ads served on proprietary AOL pages, but counts ads that appear on AOL pages accessed via the Web.