| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 4.61 | 5.88 | 3.23 |
| 2024 | 3.24 | 4.58 | 2.47 |
| 2023 | 3.83 | 4.44 | 3.04 |
| 2022 | 3.48 | 6.17 | 2.74 |
| 2021 | 4.01 | 7.07 | 2.73 |
| 2020 | 2.94 | 4.08 | 2.61 |
| 2019 | 3.19 | 4.57 | 2.66 |
| 2018 | 3.59 | 5.47 | 2.52 |
| 2017 | 6.21 | 6.86 | 4.9 |
| 2016 | 7.26 | 10.14 | 6.36 |
| 2015 | 8.68 | 14.18 | 4.37 |
| 2014 | 4.27 | 5.37 | 3.3 |
| 2013 | 4.34 | 5.24 | 3.7 |
| 2012 | 4.53 | 6.84 | 2.75 |
| 2011 | 5.21 | 7.04 | 2.9 |
| 2010 | 5.61 | 7.75 | 4.02 |
| 2009 | 3.87 | 6.64 | 2.43 |
| 2008 | 2.62 | 4.15 | 1.39 |