The Airline Quality Rating (AQR) is the most comprehensive study of the performance and quality of the largest airlines in the United States. The rating is a multifactor look of the airlines based on mishandled baggage, consumer complaints, on-time performance and involuntary denied boardings. The Airline Quality Rating industry score for 2015 shows an industry that improved slightly in overall performance quality over the previous year. Six airlines (Delta, ExpressJet, JetBlue, SkyWest, Southwest, and United) showed improvement in AQR scores in 2015. ExpressJet and SkyWest had the largest improvements in their AQR scores for 2015