| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2021 | 5.07 | 6.06 | 4.37 |
| 2020 | 5.84 | 7.58 | 4.84 |
| 2019 | 8.38 | 10.07 | 6.88 |
| 2018 | 10.57 | 14.03 | 8.75 |
| 2017 | 14.94 | 17.7 | 13.27 |
| 2016 | 14.56 | 20.34 | 12.08 |
| 2015 | 26.79 | 46.28 | 16.03 |
| 2014 | 7.08 | 19.54 | 5.29 |
| 2013 | 7.55 | 9.81 | 5.95 |
| 2012 | 9.08 | 10.48 | 7.82 |
| 2011 | 11.45 | 14.85 | 8.77 |
| 2010 | 17.14 | 28.25 | 11.58 |
| 2009 | 64.41 | 99.82 | 27.11 |
| 2008 | 34.85 | 52.92 | 26.12 |