| 年份 | 乡镇个数(个） |
| 2024 | |
| 2023 | |
| 2022 | |
| 2022 | |
| 2021 | |
| 2021 | |
| 2020 | 23 |
| 2020 | 23 |
| 2019 | 23 |
| 2018 | 23 |
| 2017 | 23 |
| 2016 | 23 |
| 2015 | 23 |
| 2014 | |
| 2014 | 24 |
| 2013 | |
| 2013 | 24 |
| 2012 | 24 |
| 2012 | 24 |
| 2011 | 24 |
| 2011 | 24 |
| 2010 | |
| 2010 | 24 |
| 2009 | |
| 2009 | 24 |
| 2008 | |
| 2008 | 24 |
| 2007 | |
| 2007 | 24 |
| 2006 | |
| 2006 | 24 |
| 2005 | |
| 2005 | 24 |
| 2004 | |
| 2004 | 24 |
| 2003 | |
| 2003 | 23 |
| 2002 | |
| 2002 | 23 |
| 2001 | |
| 2001 | 24 |
| 2000 | |
| 2000 | 23 |
| 1999 | |
| 1999 |
