Net Cash Provided by (Used in) Investing Activities
Millions
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018*** 2019 2020
AMR Corp             (3,275)             (4,740)             (1,393)                (645)             (1,048)             (1,539)             (1,365)                (234)               1,055             (2,684)             (1,692)       (1,116)       (1,571)       (3,814)       (2,911)       (5,594)       (5,698)       (3,626)       (1,973)       (2,243)       (4,342)
Continental Airlines Inc**                  (68)                (774)                  (36)                    53                    53                    51                  366                  760                    16                    78                     -                 -                 -                 -                 -                 -                 -                 -                 -                 -                 -  
Delta Air Lines Inc             (3,396)             (2,696)             (1,109)                (362)                (320)                    22                (361)                (625)               1,598             (1,008)             (2,026)       (1,498)       (1,962)       (2,756)       (2,463)       (3,955)       (2,155)       (5,366)       (4,393)       (4,563)       (9,238)
Northwest Airlines Corp                (579)                (730)             (1,780)             (2,001)                (473)                  609                (328)                (396)                (879)                     -                       -                 -                 -                 -                 -                 -                 -                 -                 -                 -                 -  
UAL Corp**             (2,521)             (1,969)                    71                  339                (296)                (291)                (250)             (2,560)               2,721                  (80)               3,320       (1,799)       (1,975)       (2,022)       (2,331)       (2,607)       (3,238)       (3,930)       (4,455)       (4,560)              50
US Airways Group Inc I             (2,001)                (867)                    22                (511)                    83                     -                       -                       -                       -                       -                       -                 -                 -                 -                 -                 -                 -                 -                 -                 -                 -  
US Airways Group Inc II                     -                       -                       -                       -                       -                       -                  (903)                  269                (915)                (495)                    63          (472)          (844)        2,148               -                 -                 -                 -                 -                 -                 -  
America West Holdings Corp                (204)                (206)                    (6)                (492)                    16                     -                       -                       -                       -                       -                       -                 -                 -                 -                 -                 -                 -                 -                 -                 -                 -  
Midwest Air Group Inc                  (56)                  (59)                  (56)                    (7)                    13                      2                      1                     -                       -                       -                       -                 -                 -                 -                 -                 -                 -                 -                 -                 -                 -  
  --sub Network and Regional            (12,100)           (12,041)             (4,287)             (3,626)             (1,972)             (1,146)             (2,840)             (2,786)              3,596             (4,189)                (335)       (4,885)       (6,352)       (6,444)       (7,705)    (12,156)    (11,091)    (12,922)    (10,821)    (11,366)    (13,530)
Southwest Airlines Co             (1,135)                (998)                (603)             (1,619)             (1,658)             (1,146)             (1,495)             (1,529)                (978)             (1,569)             (1,265)       (1,051)          (803)       (1,384)       (1,727)       (1,913)       (2,272)       (2,408)       (2,038)          (303)            (16)
AirTran Holdings Inc                      4                  (31)                      8                  (65)                  (73)                  (80)                (252)                  (83)                  329                  (47)                    24               -                 -                 -                 -                 -                 -                 -                 -                 -                 -  
JetBlue Airways Corp                (241)                (365)                (880)                (987)                (720)             (1,276)             (1,307)                (734)                (247)                (457)                (696)          (502)          (867)          (476)          (379)       (1,134)       (1,045)          (975)       (1,156)       (1,129)       (1,349)
Alaska Air Group Inc                (478)                (218)                (361)                (638)                (392)                (481)                (533)                (602)                (581)                (657)                (295)          (403)          (645)          (698)          (541)          (930)       (2,622)       (1,132)          (631)          (791)          (593)
Hawaiian Holdings Inc                  (53)                    (9)                    (8)                    (3)                     -                      83                (261)                  (31)                  (16)                  (36)                (109)          (282)          (291)          (342)          (687)            (35)          (154)          (295)          (316)          (405)            (99)
  --sub Hybrid              (1,903)             (1,621)             (1,844)             (3,312)             (2,843)             (2,900)             (3,847)             (2,979)             (1,494)             (2,767)             (2,341)       (2,238)       (2,606)       (2,900)       (3,334)       (4,012)       (6,093)       (4,810)       (4,141)       (2,628)       (2,057)
Frontier Airlines Holdings Inc*                  (34)                (135)                (198)                (194)                    15                  (96)                (141)                (295)                  249                     -                       -                 -                 -                 -                 -                 -                 -                 -                 -                 -                 -  
Spirit Airlines, Inc.                     -                       -                       -                       -                       -                       -                       -                       -                       -                       -                    (30)            (67)            (27)            (90)          (302)          (701)          (826)          (792)          (784)          (457)          (554)
  -- sub ULCC                   (34)                (135)                (198)                (194)                    15                  (96)                (141)                (295)                  249                     -                    (30)            (67)            (27)            (90)          (302)          (701)          (826)          (792)          (784)          (457)          (554)
 Total All Sectors            (14,038)           (13,796)             (6,330)             (7,132)             (4,800)             (4,142)             (6,828)             (6,059)              2,352             (6,956)             (2,706)       (7,190)       (8,985)       (9,434)    (11,341)    (16,870)    (18,010)    (18,524)    (15,746)    (14,451)    (16,141)
* Frontier Airlines Inc before 2006. Year end March 31 treated as the year before.
** United and Continental are assumed as a single carrier beginning October 1, 2010
*** Note: In 2018, many airlines changed their accounting principles to conform to new standards, which lead to some significant changes in the numbers reported compared to previous years. For the sake of clarity, many airlines provided recast 2017 results in their 10-K reports that  
       can be found in SEC’s EDGAR tool.
Note: Zero value might also mean data not reported.
Data Source:  SEC 10K Filings