| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 4.8 | 8.4 | 2.17 |
| 2024 | 2.7 | 4.86 | 1.51 |
| 2023 | 5.06 | 5.93 | 4.2 |
| 2022 | 4.68 | 6.8 | 3.32 |
| 2021 | 3.06 | 3.8 | 2.47 |
| 2020 | 3.96 | 5.04 | 3.03 |
| 2019 | 3.13 | 4.39 | 2.21 |
| 2018 | 2.71 | 3.38 | 2.11 |
| 2017 | 3.89 | 5.67 | 3.02 |
| 2016 | 7.23 | 10.62 | 5.33 |
| 2015 | 10.6 | 24.93 | 4.69 |
| 2014 | 5.24 | 8.51 | 3.93 |
| 2013 | 3.64 | 5.24 | 2.44 |
| 2012 | 2.94 | 3.55 | 2.36 |
| 2011 | 5.01 | 6.89 | 3.03 |
| 2010 | 5.39 | 6.75 | 3.83 |
| 2009 | 4.84 | 6.87 | 3.91 |
| 2008 | 4.97 | 7.02 | 2.9 |