| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.32 | 2.81 | 2.01 |
| 2024 | 2.05 | 2.71 | 1.6 |
| 2023 | 2.99 | 3.7 | 2.47 |
| 2022 | 3.25 | 5.88 | 2.35 |
| 2021 | 2.18 | 2.59 | 1.9 |
| 2020 | 3.04 | 4.03 | 2.33 |
| 2019 | 2.67 | 3.38 | 2.1 |
| 2018 | 2.73 | 3.99 | 1.88 |
| 2017 | 4.19 | 5.34 | 3.44 |
| 2016 | 7.14 | 10.79 | 5.22 |
| 2015 | 11.54 | 22.52 | 7.16 |
| 2014 | 8.65 | 10.56 | 6.85 |
| 2013 | 6.79 | 8.61 | 4.96 |
| 2012 | 5.78 | 7.05 | 4.47 |
| 2011 | 8.93 | 12.93 | 6.09 |
| 2010 | 12.37 | 14.91 | 9.45 |
| 2009 | 6.19 | 12.21 | 3.41 |
| 2008 | 4.57 | 7.95 | 2.13 |