| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2018 | 18.18 | 29.34 | 6.94 |
| 2017 | 17.35 | 24.31 | 14.5 |
| 2016 | 14.20 | 19.24 | 10.79 |
| 2015 | 14.53 | 22.04 | 10.53 |
| 2014 | 9.11 | 13.44 | 6.82 |
| 2013 | 13.43 | 17.59 | 10.64 |
| 2012 | 16.38 | 20.78 | 12.4 |
| 2011 | 27.91 | 33.25 | 19.44 |
| 2010 | 32.21 | 49.2 | 22.53 |
| 2009 | 20.00 | 28.74 | 13.01 |
| 2008 | 25.23 | 42.24 | 8.8 |
| 2007 | 25.27 | 42.09 | 12.2 |