News Summary: Yahoo's 1Q showing lets down Street

BACKTRACKING: A drop in Yahoo's ad revenue during the first three months of the year overshadowed a 36 percent increase in earnings that topped analyst forecasts. The ad decline disappointed investors hoping Yahoo Inc. would build on some of the recent momentum shown under CEO Marissa Mayer, who left Google Inc. to join the company nine months ago.

MARKET REACTION: Yahoo's stock fell by more than 4 percent in Tuesday's extended trading after the numbers came out.

PATIENCE, PLEASE: Mayer assured analysts that Yahoo is on the right track. She said the company is engaged in a "series of sprints" that will culminate in more robust growth.