Operating expense per available seat mile, excluding fuel, other non-airline operating expenses, and special items ("CASM ex-fuel") CASM is a common metric used in the airline industry. Our CASM for the relevant periods are summarized in the table below. We exclude aircraft fuel, operating expenses related to other non-airline businesses, such as JetBlue Technology Ventures and JetBlue Travel Products, and special items from total operating expenses to determine Operating expenses ex-fuel, which is a non-GAAP financial measure, and we exclude the same items from CASM to determine CASM ex-fuel, which is also a non-GAAP financial measure. We believe the impact of these special items distorts our overall trends and that our metrics are more comparable with the presentation of our results excluding such impact.