• by Wendy Davis  @wendyndavis, January 19, 2006

Marketers served 123.6 billion display ads online last month--up about 7 percent from November, according to new data from Nielsen//NetRatings AdRelevance. Despite the holiday surge, the total volume was still down slightly from the high for the year--124.5 billion, reached in October.

E-mail sites continued to grow in popularity with marketers last month, garnering 32.1 percent of impressions--up both from last year's 20.1 percent and November's 26.7 percent. Portals and search engines claimed 12.1 percent of impressions, down from last year's 16.9 percent; general community sites accounted for 8.1 percent, compared to 5.3 percent last year.

Specifically, Yahoo! Mail accounted for the largest share of ads, 21.7 percent--up from last year's 7.9 percent and November's 16.7 percent. Much of that increase was driven by Vonage Holdings Corp., which appears to have dramatically increased its advertising on Yahoo! Mail, according to a Nielsen//NetRatings representative.

MSN Hotmail garnered 7.5 percent of impressions, compared to last year's 7.7 percent and November's 7.9 percent. Myspace, while still relatively popular with advertisers, drew 4.8 percent of ads--down considerably from a yearly high point of September, when the social networking site commanded 12.4 percent of online ads.

Financial services advertisers accounted for 20 percent of impressions last month--the same as in December 2004. Telecoms also were responsible for 20 percent of online ads, almost double last year's 12 percent. Retail goods and services marketers accounted for 15 percent of impressions, down from last year's 19 percent.

Nielsen//NetRatings also looked at impressions just within the health category--which claimed about 4 percent of all display ads in November. Novartis AG was the largest advertiser, accounting for 16.2 percent of health ads--almost triple last year's 6.7 percent. Pfizer, Inc. grew its market share to 12.6 percent, from last year's 1.8 percent, while the third-largest health advertiser--Weight Watchers International, Inc.--accounted for just 7.5 percent of ads in the category, compared to last year's 15.1 percent.

Nielsen//NetRatings' AdRelevance doesn't include in the data ads served on proprietary America Online pages, accessed only by AOL subscribers--but counts ads that appear on AOL pages accessed via the Web.

Online Display Impressions March--November 2005

Month	Impressions Served (bil)
March	97.1
April	91.4
May	93.1
June	97.1
July	102.9
August	112.1
September	110.2
October	124.5
November	115.2
December	123.6

Source: Nielsen//NetRatings AdRelevance