| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 5.21 | 5.56 | 4.79 |
| 2024 | 4.96 | 6.59 | 4.25 |
| 2023 | 5.22 | 5.94 | 4.62 |
| 2022 | 4.83 | 5.55 | 3.75 |
| 2021 | 6.1 | 8.59 | 5.03 |
| 2020 | 8 | 10.48 | 6.16 |
| 2019 | 9.34 | 13.7 | 6.61 |
| 2018 | 6.53 | 8.29 | 5.08 |
| 2017 | 8.34 | 9.8 | 7.08 |
| 2016 | 7.67 | 9.56 | 6.38 |
| 2015 | 23.43 | 40.64 | 8.41 |
| 2014 | 21.25 | 37.8 | 16.33 |
| 2013 | 15.52 | 21.58 | 11.2 |
| 2012 | 12.34 | 20.13 | 7.41 |
| 2011 | 8.5 | 10.41 | 6.63 |
| 2010 | 14 | 27.22 | 8.21 |
| 2009 | 31.52 | 44.41 | 23.86 |
| 2008 | 22.24 | 29.59 | 13.34 |
| 2007 | 21 | 45.04 | 3.63 |
| 2006 | 16.51 | 28.89 | 8 |