| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.65 | 0.7 | 0.6 |
| 2024 | 0.57 | 0.71 | 0.43 |
| 2023 | 0.56 | 0.67 | 0.44 |
| 2022 | 0.56 | 0.76 | 0.42 |
| 2021 | 0.6 | 0.8 | 0.43 |
| 2020 | 0.73 | 0.9 | 0.57 |
| 2019 | 0.73 | 1 | 0.58 |
| 2018 | 0.98 | 1.39 | 0.6 |
| 2017 | 1.85 | 2.91 | 1.19 |
| 2016 | 2.5 | 3.16 | 1.6 |
| 2015 | 2.15 | 3.57 | 1.05 |
| 2014 | 0.97 | 1.19 | 0.83 |
| 2013 | 0.88 | 1.09 | 0.7 |
| 2012 | 0.65 | 0.88 | 0.49 |
| 2011 | 0.84 | 1.15 | 0.52 |