| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2018 | 27.39 | 40.27 | 15.11 |
| 2017 | 23.27 | 36.06 | 15.21 |
| 2016 | 17.36 | 21.3 | 12.57 |
| 2015 | 15.57 | 20.2 | 12.5 |
| 2014 | 11.51 | 14.14 | 9.41 |
| 2013 | 9.90 | 13.7 | 7.03 |
| 2012 | 12.65 | 14.66 | 9.29 |
| 2011 | 21.67 | 24.91 | 18.88 |
| 2010 | 26.26 | 35.21 | 20.35 |
| 2009 | 23.98 | 37.67 | 16.06 |
| 2008 | 48.52 | 98.13 | 25.2 |
| 2007 | 78.75 | 131.9 | 42.27 |