| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 6.06 | 7.98 | 4.94 |
| 2024 | 4.51 | 5.94 | 3.47 |
| 2023 | 5.99 | 8.28 | 4.59 |
| 2022 | 4.31 | 6.32 | 2.92 |
| 2021 | 3.67 | 4.68 | 3.16 |
| 2020 | 4.14 | 5.43 | 2.94 |
| 2019 | 4.02 | 5.49 | 3.35 |
| 2018 | 4.77 | 7.79 | 2.96 |
| 2017 | 6.85 | 8.04 | 5.58 |
| 2016 | 8.08 | 11.4 | 6.56 |
| 2015 | 7.3 | 12.35 | 4.06 |
| 2014 | 3.73 | 5.37 | 2.57 |
| 2013 | 2.3 | 3.68 | 1.85 |
| 2012 | 1.9 | 2.59 | 1.59 |
| 2011 | 2.9 | 4.08 | 1.79 |
| 2010 | 3.48 | 4.18 | 2.58 |
| 2009 | 3 | 3.98 | 2.04 |
| 2008 | 2.14 | 3.29 | 1.11 |