| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2026 | 4.25 | 4.7 | 3.7 |
| 2025 | 4.67 | 5.8 | 3.85 |
| 2024 | 2.88 | 4.4 | 2.04 |
| 2023 | 3.31 | 4.21 | 2.77 |
| 2022 | 2.72 | 3.41 | 2.22 |
| 2021 | 2.79 | 3.11 | 2.4 |
| 2020 | 3.94 | 5.13 | 3.03 |
| 2019 | 3.8 | 5.07 | 3 |
| 2018 | 3.66 | 5.66 | 2.77 |
| 2017 | 6.05 | 7.96 | 4.45 |
| 2016 | 7.93 | 11.22 | 6.88 |
| 2015 | 9.14 | 13.77 | 4.94 |
| 2014 | 5.31 | 7.66 | 3.88 |
| 2013 | 2.63 | 4.05 | 1.68 |
| 2012 | 1.92 | 2.63 | 1.43 |
| 2011 | 2.59 | 3.73 | 2.06 |
| 2010 | 4.34 | 6.12 | 3.37 |
| 2009 | 2.99 | 4.02 | 1.97 |
| 2008 | 2.56 | 4.6 | 1.38 |