The cancellation of more than 2,000 Southwest Airlines flights due to a computer outage last month will cost the carrier an estimated $54 million.

The Dallas Morning News reported the lost revenue and increased cost estimates based on a Southwest investor advisory released Wednesday.

Dallas-based Southwest blamed a router failure for the July 20 outage and subsequent days of delays.

While Southwest didn’t provide a specific cost of the outage, the company said it would lead to a 0.5 percentage point drop in unit revenues during the third quarter and that it expects its cost per seat mile to rise by up to 2 percent. The newspaper based its estimate on those projections.

An unrelated computer outage this week has resulted in the cancellation of more than 2,100 Delta Air Lines flights.

(AP)