Here is the retirement schedule for AA:

Year Total
10/14/2006 - 12/31/2006 60
01/01/2007 - 12/31/2007 281
01/01/2008 - 12/31/2008 402
01/01/2009 - 12/31/2009 405
01/01/2010 - 12/31/2010 363
01/01/2011 - 12/31/2011 318
01/01/2012 - 12/31/2012 312
01/01/2013 - 12/31/2013 388
01/01/2014 - 12/31/2014 478
01/01/2015 - 12/31/2015 571
01/01/2016 - 12/31/2016 628
01/01/2017 - 12/31/2017 683
01/01/2018 - 12/31/2018 733
01/01/2019 - 12/31/2019 733
01/01/2020 - 12/31/2020 744
01/01/2021 - 12/31/2021 718
01/01/2022 - 12/31/2022 595
01/01/2023 - 12/31/2023 503
01/01/2024 - 12/31/2024 479
01/01/2025 - 12/31/2025 412
01/01/2026 - 12/31/2026 442

You can see that there is no 'Vietnam era' bulge...that's over and done with. The increase in the 2018 area is due to the increased hiring in the mid to late 80s and typify the hiring trends then of hiring ex-mil folks.