✳点击上方数值可查看历史数据
| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2018 | 6.46 | 8.13 | 5.78 |
| 2017 | 6.50 | 7.38 | 5.86 |
| 2016 | 6.04 | 6.96 | 5.58 |
| 2015 | 7.48 | 9.65 | 6.01 |
| 2014 | 4.52 | 7.05 | 4.04 |
| 2013 | 5.03 | 5.73 | 4.52 |
| 2012 | 5.77 | 6.17 | 5.17 |
| 2011 | 7.03 | 7.78 | 6.41 |
| 2010 | 9.16 | 10.62 | 7.83 |
| 2009 | 12.15 | 14.98 | 9.17 |
| 2008 | 17.33 | 27.61 | 11.87 |
| 2007 | 25.95 | 33.77 | 19.95 |
| 2006 | 20.91 | 32.34 | 19.24 |