| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 4.02 | 5.27 | 3.48 |
| 2024 | 3.71 | 5.27 | 3.04 |
| 2023 | 5.13 | 8.32 | 4.21 |
| 2022 | 2.97 | 8.32 | 2.18 |
| 2021 | 2.6 | 3.31 | 2.15 |
| 2020 | 2.31 | 2.84 | 1.73 |
| 2019 | 2.33 | 2.79 | 2.02 |
| 2018 | 2.89 | 3.79 | 2.24 |
| 2017 | 4.3 | 5.24 | 3.56 |
| 2016 | 4.43 | 4.97 | 3.88 |
| 2015 | 5.16 | 7.8 | 4.01 |
| 2014 | 5.7 | 7.5 | 4.32 |
| 2013 | 5.14 | 7.06 | 4.27 |
| 2012 | 5.37 | 6.11 | 4.66 |
| 2011 | 5.42 | 6.64 | 4.74 |
| 2010 | 6.25 | 7.63 | 4.93 |
| 2009 | 5.98 | 7.31 | 4.78 |
| 2008 | 7.05 | 11.52 | 3.27 |