| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.67 | 0.82 | 0.51 |
| 2024 | 0.56 | 0.68 | 0.46 |
| 2023 | 0.71 | 0.78 | 0.62 |
| 2022 | 0.91 | 1.4 | 0.7 |
| 2021 | 1.78 | 2.8 | 1.11 |
| 2020 | 2.43 | 4.21 | 1.4 |
| 2019 | 1.71 | 2.11 | 1.39 |
| 2018 | 6.39 | 13.64 | 1.92 |
| 2017 | 4.49 | 5.01 | 3.96 |
| 2016 | 4.75 | 5.87 | 4.08 |
| 2015 | 5.75 | 9 | 3.9 |
| 2014 | 4.4 | 6.57 | 2.59 |
| 2013 | 2.98 | 3.84 | 2.09 |
| 2012 | 2.28 | 3.06 | 1.76 |
| 2011 | 2.82 | 3.16 | 2.31 |