Delta Air Lines Inc. said a key measure of revenue rose 5.5 percent in September as traffic rose.

The gain in revenue for each seat flown one mile was due in part to strong results in U.S. flying and flights across the Atlantic.

The gains would have been higher if not for a weaker Japanese yen. Delta has a hub in Tokyo and sells some tickets in yen, so a lower yen hurts that revenue. The weaker yen hurt its revenue gain by 1 percentage point, which is less damage than it did in August.

Delta's worldwide traffic rose 1.8 percent for September. Domestic traffic rose 1 percent. International traffic was up 2.8 percent, with strong gains in Latin America and increasing traffic across the Atlantic offsetting a 1 percent decline in Pacific flying.

Flying capacity rose 1.7 percent.

Occupancy rose a tenth of a percentage point to 83.3 percent.

For the first nine months of the year, Delta's traffic has risen 0.7 percent. It has boosted flying capacity by 0.4 percent. Its occupancy has risen three-tenths of a percentage point to 84.2 percent.