| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 4.09 | 4.37 | 3.83 |
| 2024 | 4.82 | 5.86 | 4.29 |
| 2023 | 6 | 7.3 | 5 |
| 2022 | 3.85 | 6.13 | 2.83 |
| 2021 | 4.21 | 5.13 | 3.53 |
| 2020 | 4.17 | 5.87 | 2.48 |
| 2019 | 2.91 | 3.69 | 2.27 |
| 2018 | 4.43 | 6.08 | 2.42 |
| 2017 | 4.52 | 5.03 | 4.14 |
| 2016 | 4.04 | 4.93 | 3.19 |
| 2015 | 5.28 | 7.94 | 4.02 |
| 2014 | 4 | 4.79 | 3.25 |
| 2013 | 3.86 | 4.59 | 3.22 |
| 2012 | 3.14 | 3.79 | 2.58 |
| 2011 | 3.49 | 4.53 | 2.88 |
| 2010 | 4.2 | 5.27 | 3.21 |
| 2009 | 2.84 | 3.67 | 2.06 |