Delta Air Lines ranked third in on-time arrivals in August in the latest monthly federal report, as the carrier continues its focus on improving performance.

In a comparison of 15 U.S. air carriers, about 83.9 percent of Delta’s flights in August arrived on time, putting it behind only Hawaiian and Alaska Airlines. That marked an improvement over Delta’s sixth-place ranking in the same month last year.

Meanwhile, AirTran ranked seventh with an 81.7 percent on-time arrival rate in August. Southwest ranked ninth at 79.6 percent.

But for the year through August, AirTran ranked third, while Delta ranked fifth and Southwest came in seventh.

Atlanta-based Delta has been working for the last couple of years to get flights out on time more often. It improved its on-time ranking from 15th in 2010 to fifth in 2011.

“There was a concerted effort across the company,” said Delta spokesman Morgan Durrant.

As part of Delta’s employee incentive program for on-time performance, the company has paid the maximum level of bonuses to employees for the past 13 months.