| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2024 | 5.96 | 7.6 | 4.57 |
| 2023 | 7.56 | 11.44 | 4.84 |
| 2022 | 5.7 | 8 | 4.26 |
| 2021 | 9.27 | 11.7 | 7.64 |
| 2020 | 7.15 | 8.59 | 6.27 |
| 2019 | 8.29 | 10.76 | 6.29 |
| 2018 | 8.59 | 11.16 | 5.63 |
| 2017 | 7.79 | 11.97 | 4.97 |
| 2016 | 5.95 | 7.07 | 5.12 |
| 2015 | 10.8 | 18.32 | 6.19 |
| 2014 | 6.55 | 8.35 | 5.13 |
| 2013 | 10.56 | 21.15 | 6.25 |
| 2012 | 7.89 | 9.6 | 6.05 |
| 2011 | 12.9 | 22.19 | 6.93 |
| 2010 | 13.15 | 23.39 | 8.9 |
| 2009 | 9.07 | 12.46 | 6.13 |