| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.63 | 3 | 2.31 |
| 2024 | 2.66 | 3.55 | 1.83 |
| 2023 | 4.7 | 7.35 | 3.42 |
| 2022 | 6.61 | 9.34 | 4.62 |
| 2021 | 5.34 | 11 | 2.98 |
| 2020 | 4.22 | 6.04 | 3.06 |
| 2019 | 5.1 | 6.9 | 3.6 |
| 2018 | 4.68 | 7.05 | 3.36 |
| 2017 | 6.28 | 13.72 | 2.78 |
| 2016 | 11.25 | 17.85 | 9.51 |
| 2015 | 23.5 | 31.81 | 11.91 |
| 2014 | 12.9 | 24.64 | 8.33 |
| 2013 | 5.74 | 9.75 | 3.22 |
| 2012 | 4.52 | 6.45 | 2.37 |
| 2011 | 7.37 | 9.68 | 5.71 |
| 2010 | 8.43 | 10.57 | 5.4 |
| 2009 | 6.49 | 9.27 | 4.08 |