$^{(h)}$  Includes minimum pension contributions based on actuarially determined estimates and is based on estimated payments through 2028. The total AAG expected pension contribution of $807 million in 2019 assumes a supplemental contribution of $21 million in addition to the $786 million minimum required contribution. $^{(i)}$  Includes purchase commitments for jet fuel, construction projects and information technology support. Capital Raising Activity and Other Possible Actions In light of our significant financial commitments related to, among other things, new aircraft, the servicing and amortization of existing debt and equipment leasing arrangements, and future pension funding obligations, we and our subsidiaries will regularly consider, and enter into negotiations related to, capital raising activity, which may include the entry into leasing transactions and future issuances of secured or unsecured debt obligations or additional equity securities in public or private offerings or otherwise. The cash available from operations and these sources, however, may not be sufficient to cover cash contractual obligations because economic factors may reduce the amount of cash generated by operations or increase costs. For instance, an economic downturn or general global instability caused by military actions, terrorism, disease outbreaks, natural disasters or other causes could reduce the demand for air travel, which would reduce the amount of cash generated by operations. An increase in costs, either due to an increase in borrowing costs caused by a reduction in credit ratings or a general increase in interest rates, or due to an increase in the cost of fuel, maintenance, or aircraft, aircraft engines or parts, could decrease the amount of cash available to cover cash contractual obligations. Moreover, certain of our financing arrangements contain significant minimum cash balance requirements. As a result, we cannot use all of our available cash to fund operations, capital expenditures and cash obligations without violating these requirements. See Note 5 to AAG’s Consolidated Financial Statements in Part II, Item 8A and Note 3 to American’s Consolidated Financial Statements in Part II, Item 8B for information regarding our financing arrangements. In the past, we have from time to time refinanced, redeemed or repurchased our debt and taken other steps to reduce or otherwise manage the aggregate amount and cost of our debt or lease obligations or otherwise improve our balance sheet. Going forward, depending on market conditions, our cash position and other considerations, we may continue to take such actions. Our Board of Directors has from time to time authorized programs to repurchase shares of our common stock, one of which is currently in effect, and may authorize additional share repurchase programs in the future. See Note 1 to AAG’s Consolidated Financial Statements in Part II, Item 8A and Note 1 to American’s Consolidated Financial Statements in Part II, Item 8B for information regarding the basis of presentation. The preparation of financial statements in accordance with GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities, revenues and expenses, and the disclosure of contingent assets and liabilities at the date of the financial statements. We believe our estimates and assumptions are reasonable; however, actual results could differ from those estimates. Critical accounting policies are defined as those that are reflective of significant judgments and uncertainties and could potentially result in materially different results under different assumptions and conditions. We have identified the following critical accounting policies that impact the preparation of our consolidated financial statements. See the “ Basis of Presentation and Summary of Significant Accounting Policies ” included in Note 1 to AAG’s Consolidated Financial Statements in Part II, Item 8A and Note 1 to American’s Consolidated Financial Statements in Part II, Item 8B for additional discussion of the application of these estimates and other accounting policies. We recognize all revenues generated from transportation on American and our regional flights operated under the brand name American Eagle, including associated baggage fees, ticketing change fees and other inflight services, as passenger revenue when transportation is provided. Ticket and other related sales for transportation that has not yet been provided are initially deferred and recorded as air traffic liability on our consolidated balance sheets. The air traffic liability principally represents tickets sold for future travel on American and partner airlines, as well as estimated future refunds and exchanges of tickets sold for past travel. The majority of tickets sold are nonrefundable. A small percentage of tickets, some of which are partially used tickets, expire unused. Due to complex pricing structures, refund and exchange policies, and interline agreements with other airlines, Passenger Revenue Critical Accounting Policies and Estimates OTHER INFORMATION Basis of Presentation 71