| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2026 | 6.85 | 7.69 | 5.87 |
| 2025 | 7.09 | 8.55 | 5.85 |
| 2024 | 4.66 | 9.03 | 3.06 |
| 2023 | 5.09 | 6.82 | 4.13 |
| 2022 | 4.81 | 6.67 | 3.51 |
| 2021 | 6.47 | 8.09 | 5.25 |
| 2020 | 8.35 | 9.85 | 6.89 |
| 2019 | 8 | 11.04 | 7.04 |
| 2018 | 10.41 | 13.98 | 7.23 |
| 2017 | 15.19 | 19.81 | 11.76 |
| 2016 | 22.03 | 26.89 | 18.48 |
| 2015 | 28.58 | 53.52 | 17.06 |
| 2014 | 14.26 | 19.28 | 10.35 |
| 2013 | 11.03 | 14.45 | 7.84 |
| 2012 | 7.46 | 8.65 | 6.3 |
| 2011 | 12.56 | 20.08 | 7.02 |
| 2010 | 11.82 | 16.13 | 9.63 |