| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 3.94 | 5.03 | 3.2 |
| 2024 | 3.24 | 4.57 | 2.46 |
| 2023 | 3.64 | 6.57 | 2.03 |
| 2022 | 2.02 | 2.98 | 1.55 |
| 2021 | 2.72 | 3.37 | 2.15 |
| 2020 | 4.91 | 8.06 | 2.81 |
| 2019 | 4.42 | 7.87 | 2.97 |
| 2018 | 5.26 | 7.76 | 3.87 |
| 2017 | 5.51 | 6.49 | 4.63 |
| 2016 | 6.6 | 8.81 | 5.28 |
| 2015 | 12.62 | 21.39 | 7.39 |
| 2014 | 9.31 | 12.19 | 7.14 |
| 2013 | 7.35 | 13.98 | 4.36 |
| 2012 | 5.63 | 8.12 | 3.42 |
| 2011 | 13.69 | 22.99 | 6.45 |
| 2010 | 26.14 | 41.26 | 21.29 |