| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 6.85 | 7.63 | 5.85 |
| 2024 | 5.76 | 8.26 | 4.41 |
| 2023 | 11.43 | 15.44 | 8.01 |
| 2022 | 16.93 | 23.34 | 13.84 |
| 2021 | 18.2 | 25.22 | 13.55 |
| 2020 | 15.41 | 26.17 | 9.69 |
| 2019 | 9.35 | 13.71 | 6.93 |
| 2018 | 8.48 | 11.85 | 6.95 |
| 2017 | 8.83 | 10.54 | 7.48 |
| 2016 | 8.53 | 10.57 | 6.8 |
| 2015 | 10.33 | 16.25 | 7.49 |
| 2014 | 7.38 | 8.84 | 6 |
| 2013 | 7.11 | 9.07 | 5.48 |
| 2012 | 8.11 | 12.32 | 6.22 |
| 2011 | 11.95 | 16.82 | 7.59 |
| 2010 | 14.6 | 18.46 | 11.38 |
| 2009 | 9.54 | 13.3 | 6.71 |
| 2008 | 8.73 | 13.88 | 4.68 |
| 2007 | 7.07 | 10.9 | 4.9 |
| 2006 | 6.2 | 9.15 | 4.42 |