| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 11.2 | 21.97 | 6.2 |
| 2024 | 8.6 | 15.31 | 6.01 |
| 2023 | 10.96 | 15.34 | 4.79 |
| 2022 | 4.63 | 6.33 | 2.91 |
| 2021 | 2.61 | 3.37 | 1.85 |
| 2020 | 1.99 | 2.91 | 1.46 |
| 2019 | 2.21 | 3.15 | 1.73 |
| 2018 | 3.16 | 4.43 | 1.87 |
| 2017 | 4.97 | 5.93 | 4.16 |
| 2016 | 4.64 | 6.92 | 3.94 |
| 2015 | 7.39 | 12.13 | 4.5 |
| 2014 | 4.34 | 6.59 | 3.42 |
| 2013 | 4 | 6.04 | 3.22 |
| 2012 | 7.51 | 9.94 | 3.68 |
| 2011 | 8.3 | 11.93 | 4.54 |
| 2010 | 5.04 | 6.19 | 3.58 |
| 2009 | 4.17 | 5.99 | 2.03 |
| 2008 | 4.84 | 12.11 | 1.23 |
| 2007 | 12.97 | 22.7 | 7.94 |