It marks the first monthly decline in online ad revenue the Times Co. has reported to date.

The online falloff contributed to a 20.9% drop in overall ad revenues and a 13.9% decline in the company's total revenues last month. It also signals a further chilling of the online ad market for newspapers and other Web publishers.

Within the Times' News Media Group, which includes NYTimes.com, online ad revenues fell 4% compared to a year ago. The Times said in a statement that modest growth in display ads was offset by weakness in recruiting and real estate advertising.

Despite the drop last month, ad revenue across all the Times Web businesses--spanning NYTimes.com, Boston.com and About.com, among other sites--was up 11.6% for the year-to-date through November, compared to a year ago.

Last month, Nielsen Online ranked the Times as the 10th-largest Web property, with 55 million unique visitors--up 11% from the year-earlier period. comScore estimated the Times online audience to be somewhat lower, at 47.3 million unique visitors--making it the 16th- largest Web property.

During its third-quarter conference call with analysts on Oct. 23, Times executives expressed a commitment to expanding initiatives on the digital side despite softening ad sales.

"In the coming months www.nytimes.com will expand its small business, personal technology and your money sections, introduce more journalists, deepen coverage in its deal book franchise, and continue to add new tools and multimedia features," said Janet L. Robinson, president and CEO of the Times Co.

The company is counting on rising digital revenues to offset the long-term decline in print advertising and circulation battering the entire newspaper industry. To weather the economic downturn, the Times Co. said earlier this month that it plans to shore up its finances by paying off $400 million owed on one line of credit in May.

That will be achieved partly by mortgaging its headquarters for $225 million--and cutting its dividend, for another $100 million.

The Times Co. is also said to be trying to sell its 17.5% stake in the holding company that owns the Boston Red Sox. That could bring in at least $200 million, according to a Reuters last week, citing newspaper publishers, analysts and sports bankers.

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