April 4 (Reuters) - Delta Air Lines Inc on Tuesday lowered its forecast for a closely watched revenue metric, citing slower-than-expected improvement in average fares for flights booked at the last minute.
The No. 2 U.S. airline said it expects passenger unit revenue - which compares sales to flight capacity - to fall about 0.5 percent in the first quarter ended March. (bit.ly/2oVfqGu)
The airline had previously expected first-quarter passenger unit revenue to be about flat.
Delta's shares were down 1.1 percent at $45.80 in premarket trading. (Reporting by Ankit Ajmera in Bengaluru; Editing by Sai Sachin Ravikumar)