| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 6.6 | 7.52 | 5.58 |
| 2024 | 5.47 | 7.2 | 3.96 |
| 2023 | 6.9 | 8.08 | 5.79 |
| 2022 | 7.4 | 9.59 | 5.64 |
| 2021 | 7.1 | 9.39 | 5.4 |
| 2020 | 8.29 | 13.41 | 5.96 |
| 2019 | 7.47 | 10.81 | 5.36 |
| 2018 | 6.42 | 9.1 | 3.77 |
| 2017 | 11.99 | 16.06 | 8.3 |
| 2016 | 20.59 | 33.25 | 14.88 |
| 2015 | 27.6 | 57.89 | 12.02 |
| 2014 | 8.99 | 12.69 | 6.46 |
| 2013 | 5.39 | 7.14 | 4.23 |
| 2012 | 6.61 | 10.53 | 4.15 |
| 2011 | 15.07 | 20.58 | 9.07 |
| 2010 | 22.24 | 29.59 | 17.28 |