ULCC +81.2%. Delta Air Lines +51.6%, Southwest Airlines +36.9%, United Airlines +18.8%, American Airlines −5.3%. Weekly closes, Nov 7, 2025 = 100, log scale.

End-of-day closes (Databento EOD), the last close of each week. The four peers are the largest US-listed companies by market value in ULCC’s SEC industry (Air Transportation, Scheduled) with a year of closes. It shows what the closes did; a move here is not a cause, a forecast or a call.