Delta Air Lines ranked second in its category in a closely-watched J.D. Power study released Wednesday.

Alaska Airlines again took the top spot in the “traditional carrier” category ahead of Delta, which has now been in the No. 2 spot for three years in a row.

Earning the top J.D. Power award in the category has long been an aspiration set by Delta CEO Richard Anderson and outlined in the company’s annual goals. Delta improved in all seven categories of the study, but remained 10 points behind Alaska’s score of 719 on a scale of 1,000. The J.D. Power study measures passenger satisfaction with airlines based on cost and fees, in-flight services, boarding/deplaning/baggage, flight crew, aircraft, check-in and reservation.

A benefit of providing good service is that “passenger are generally less critical when there is a departure delay or a late arrival,” J.D. Power’s global travel and hospitality lead Rick Garlick said in a written statement.

In the low-cost carrier category, JetBlue took the No. 1 position of 801, which also made it the highest scoring airline overall.