Key TakeawaysAmerican Eagle Outfitters posted weaker-than-expected revenue and guidance as sales at its secondary brands declined.The young adult clothing retailer gave a soft outlook for current quarter revenue and operating income.The company's shares were down on the news, and in the red for the year so far. Shares of American Eagle Outfitters (AEO) fell after the young adult clothing retailer’s sales missed forecasts and it gave a soft outlook for the current quarter as its smaller brands struggled.  T ...