| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2018 | 20.48 | 27.58 | 16.34 |
| 2017 | 21.68 | 30.58 | 16.43 |
| 2016 | 20.40 | 23.4 | 16.9 |
| 2015 | 15.14 | 18.89 | 9.72 |
| 2014 | 15.44 | 26.49 | 12.37 |
| 2013 | 18.10 | 22.51 | 15.07 |
| 2012 | 34.68 | 40.16 | 29.42 |
| 2011 | 22.00 | 25.95 | 18.51 |
| 2010 | 24.13 | 28.81 | 20.68 |
| 2009 | 21.70 | 30.42 | 12.41 |
| 2008 | 131.36 | 282.87 | 60.27 |
| 2007 | 55.26 | 56.2 | 53.81 |