| 序号 | 时间 (年) |
数据 (人/户) |
|---|---|---|
| 1 | 2021 | |
| 2 | 2020 | |
| 3 | 2019 | |
| 4 | 2018 | |
| 5 | 2017 | |
| 6 | 2016 | |
| 7 | 2015 | 3.07 |
| 8 | 2014 | 3.13 |
| 9 | 2013 | 3.60 |
| 10 | 2012 | 3.62 |
| 11 | 2011 | 3.64 |
| 12 | 2010 | 3.64 |
| 13 | 2009 | 3.63 |
| 14 | 2008 | 3.95 |
| 15 | 2005 | 3.91 |
| 16 | 2000 | 3.86 |
| 17 | 1995 | 4.00 |
