| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.5 | 2.29 | 1.25 |
| 2024 | 1.22 | 1.45 | 0.95 |
| 2023 | 1.42 | 1.7 | 1.21 |
| 2022 | 1.5 | 2.77 | 0.93 |
| 2021 | 1.12 | 1.32 | 0.99 |
| 2020 | 1.13 | 1.57 | 0.79 |
| 2019 | 1.04 | 1.49 | 0.88 |
| 2018 | 1.1 | 1.3 | 0.86 |
| 2017 | 1.27 | 1.64 | 1.12 |
| 2016 | 1.2 | 1.43 | 0.92 |
| 2015 | 1.82 | 2.91 | 1.05 |
| 2014 | 1.74 | 2.8 | 1.26 |
| 2013 | 1.17 | 1.45 | 0.84 |
| 2012 | 3.97 | 11 | 1.03 |
| 2011 | 5.46 | 10.07 | 4.37 |
| 2010 | 4.63 | 5.99 | 3.32 |
| 2009 | 5.48 | 6.43 | 4.33 |