Yahoo will lay off at least 10% of its global staff before the end of the year, the company announced on Tuesday along with disappointing financial results for its third quarter.

The layoffs are the major portion of a $400 million cost-cutting plan Yahoo is implementing that also includes other measures for achieving what the company called "structural efficiencies."

(View a slideshow on the biggest IT layoffs of 2008.)

Revenue for the third quarter, which ended Sept. 30, increased only 1% to $1.768 billion compared with the same quarter in 2007.

Subtracting the commissions Yahoo pays to its advertising partners, revenue was $1.325 billion, up 3%.

Chief Financial Officer Blake Jorgensen said in Tuesday's statement that the company's revenue in the quarter was disappointing, and blamed the troubles on the tough economy and lower demand for advertising.

Net income came in at $54 million, or 4 cents per share, down from net income of $151 million, or 11 cents, in 2007's third quarter.

On a pro forma basis, which takes into account one-time items, net income was $123 million, or 9 cents per share, down from net income of $153 million, or 11 cents per share.

The IDG News Service is a Network World affiliate.