| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 9.24 | 13.61 | 8.12 |
| 2024 | 8.83 | 10.73 | 6.95 |
| 2023 | 9.23 | 14.98 | 6.95 |
| 2022 | 8.02 | 9.82 | 6.51 |
| 2021 | 8.42 | 11.14 | 6.74 |
| 2020 | 7.28 | 9.57 | 5.12 |
| 2019 | 7.33 | 9.97 | 4.83 |
| 2018 | 16.36 | 23.12 | 8.41 |
| 2017 | 18.99 | 25.29 | 16.42 |
| 2016 | 17.55 | 20.83 | 12.5 |
| 2015 | 18.97 | 27.19 | 14.33 |
| 2014 | 16.43 | 21.68 | 14.35 |
| 2013 | 22.54 | 29.44 | 17.35 |
| 2012 | 17.59 | 20.51 | 14.87 |
| 2011 | 27.2 | 34.94 | 20.86 |
| 2010 | 30.2 | 37.93 | 20.54 |
| 2009 | 25 | 32.7 | 20.87 |
| 2008 | 27.28 | 42.46 | 18.59 |
| 2007 | 25.46 | 37.6 | 8.69 |
| 2006 | 8.32 | 10.03 | 6.19 |
| 2005 | 7.9 | 10.37 | 5.68 |