| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2020 | 19.05 | 28.35 | 12.68 |
| 2019 | 32.01 | 77.84 | 18.61 |
| 2018 | 20.57 | 27.85 | 15.35 |
| 2017 | 39.17 | 52.76 | 26.27 |
| 2016 | 28.47 | 51.5 | 14.44 |
| 2015 | 26.12 | 40.11 | 15.31 |
| 2014 | 17.51 | 33.72 | 13.52 |
| 2013 | 33.04 | 68.52 | 14.03 |
| 2012 | 34.11 | 66.9 | 18.45 |
| 2011 | 16.94 | 20.57 | 14.08 |
| 2010 | 25.93 | 52.76 | 15.67 |
| 2009 | 55.42 | 80.23 | 31.92 |
| 2008 | 32.24 | 46.26 | 24.36 |