| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2018 | 10.70 | 12.99 | 8.03 |
| 2017 | 10.05 | 11.9 | 7.84 |
| 2016 | 7.33 | 8.86 | 6.13 |
| 2015 | 8.15 | 10.46 | 5.22 |
| 2014 | 6.34 | 9.06 | 4.86 |
| 2013 | 6.57 | 8.31 | 5.33 |
| 2012 | 7.54 | 9.37 | 6.03 |
| 2011 | 7.59 | 9.1 | 5.8 |
| 2010 | 9.92 | 13.66 | 7.48 |
| 2009 | 15.97 | 26.82 | 5.54 |
| 2008 | 113.42 | 281.94 | 48.42 |
| 2007 | 27.27 | 45.95 | 11.9 |