| Calendar Year | Number of Retirements | |
|---|---|---|
| 2006 | 1,212 | |
| 2007 | 1,614 | |
| 2008 | 1,473 | |
| 2009 | 4,749 | |
| 2010 | 1,224 | Details |
| 2011 | 2,947 | Details |
| 2012 | 1,396 | Details |
| 2013 | 1,972 | Details |
| 2014 | 2,199 | Details |
| 2015 | 2,106 | Details |
| 2016 | 2,535 | Details |
| 2017 | 1,485 | Details |
| 2018 | 1674 | |
| 2019 | 2,070 | |
| 2020 | 2,056 | |
| 2021 | 2,656 | |
| 2022 | 4,813 |