| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 6.69 | 8.01 | 5.6 |
| 2024 | 5.4 | 7.93 | 3.84 |
| 2023 | 5.48 | 7.09 | 4.65 |
| 2022 | 5.79 | 9.04 | 4.62 |
| 2021 | 5.88 | 8.1 | 4.51 |
| 2020 | 5.95 | 9.12 | 4.42 |
| 2019 | 4.44 | 5.3 | 3.66 |
| 2018 | 5.34 | 7.68 | 3.49 |
| 2017 | 9.81 | 14.14 | 6.98 |
| 2016 | 9.03 | 11.18 | 7.47 |
| 2015 | 12.67 | 20.01 | 7.81 |
| 2014 | 12.54 | 15.79 | 10.1 |
| 2013 | 13.66 | 17.32 | 11.1 |