During the CNBC interview, he conceded that the company's earnings forecasts had been too optimistic and that the slow economy was hurting revenue.

Compuserve charges an hourly fee for its service, so a decline in use also hurts revenue.

Instead of attracting new subscribers, the offer prompted a higher-than-expected number of existing customers to switch to lower-priced plans, hurting revenue.

Its goal is to maximize ridership without severely hurting revenue.

The possible loss of Roxiam would hurt revenue, because Merck's $2 billion-a-year heart drug, Vasotec, will shortly face stiff competition from low-cost generic versions of Bristol-Myers Squibb's Capoten, another successful heart drug.

Northwest, however, said the plan would hurt revenue in the struggling industry, where the average coast-to-coast ticket price has dropped by half in the last two years, mostly because of the growth of low-fare companies like Southwest and JetBlue.

The delistings have hurt revenue, and Nasdaq is considering layoffs, Richard G. Ketchum, its president, said yesterday.

The weak dollar and softening insurance rates are hurting revenue, the company said.

Delta said it expected the move to hurt revenue initially.

Still, she said, the company will test the impact of the text ads to make sure they do not hurt revenue.