NEW YORK (AP) — Delta Air Lines said Tuesday that its passenger revenue increased 8 percent last month, as it grabbed more higher-paying business travel and expanded service at New York's LaGuardia airport.

The Atlanta-based airline's improvement in passenger revenue per available seat mile, which measures how much an airline makes from a paying passenger flown a single mile, rose 8 percent from a year ago and was on target with a forecast from Delta last week. Delta warned then that its second-quarter earnings will be hurt by bad bets hedging on the price of fuel.

Traffic last month rose 0.4 percent, as an improvement in the U.S. was countered by a decline overseas. Traffic rose 2 percent in its core U.S. operations, but it fell 3.3 percent on regional flights.

Continued strength over the Pacific and to Latin America was offset by lower traffic across the Atlantic.

The airline's number of available seats system-wide fell 1.7 percent, which helped boost fares.

As it cut back flights and traffic improved, remaining flights were fuller. Delta's occupancy rate rose 1.8 percentage points to 88.1 percent.

Delta shares fell 35 cents, or 3.2 percent, to $10.77 in midday trading. Shares of most major airlines traded lower as oil prices spiked to the highest level since May.