| 序号 | 时间 (年) |
数据 (‰) |
|---|---|---|
| 1 | 2018 | |
| 2 | 2017 | |
| 3 | 2016 | |
| 4 | 2015 | |
| 5 | 2014 | |
| 6 | 2013 | |
| 7 | 2012 | 31.15 |
| 8 | 2011 | 27.05 |
| 9 | 2009 | 25.37 |
| 10 | 2008 | 27.72 |
| 11 | 2007 | 25.31 |
| 12 | 2006 | 18.91 |
| 13 | 2005 | 17.16 |
| 14 | 2004 | 13.69 |
| 15 | 2003 | 17.06 |
| 16 | 2002 | 16.44 |
