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What: Shares of United Continental Holdings Inc (NYSE:UAL) were falling today, down as much as 10% after posting an underwhelming earnings report this morning.

So what: The airline giant turned in an adjusted per-share loss of $1.33 as CEO Jeff Smisek said the performance was "well below what we can and should achieve." The loss was actually slightly better than estimates at $1.35, but those had been sharply reduced in recent weeks. Offering an excuse, the company blamed $200 million of the $489 million loss on severe winter weather. Revenue was down slightly, falling 0.3% to $8.7 billion, just below expectations at $8.71 billion, and revenue per average seat mile was down 2%. 

Now what: Despite the poor weather, many of United's rivals reported excellent results in the first quarter, and the company still seems to be struggling to streamline itself following its merger with Continental in 2010. Smisek acknowledged that the airline still has too many parallel technologies, and that customer service has been lacking. United has the unfortunate distinction of being more susceptible to winter weather than other airlines as all of its hubs are in cold-weather cities, and the first quarter is generally the worst in the airline industry. Investors may want to wait and see if management can improve results over the next quarter or two.

Jeremy Bowman has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.