| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 6.5 | 6.98 | 5.93 |
| 2024 | 5.03 | 7.82 | 3.82 |
| 2023 | 4.27 | 5.46 | 3.57 |
| 2022 | 3.69 | 4.67 | 2.8 |
| 2021 | 5.05 | 6.97 | 3.99 |
| 2020 | 6.07 | 8.6 | 3.43 |
| 2019 | 3.43 | 4.2 | 2.66 |
| 2018 | 3.14 | 4.29 | 2.28 |
| 2017 | 5.3 | 6.82 | 4.19 |
| 2016 | 7.21 | 10.72 | 6.25 |
| 2015 | 11.41 | 19.9 | 6.53 |
| 2014 | 4.95 | 7.81 | 3.85 |
| 2013 | 3.69 | 5.45 | 2.67 |
| 2012 | 2.98 | 3.9 | 2.03 |
| 2011 | 4.95 | 6.89 | 3.83 |
| 2010 | 5.58 | 8.17 | 3.84 |
| 2009 | 3.55 | 4.49 | 3 |
| 2008 | 5.5 | 11.97 | 2.16 |
| 2007 | 8.15 | 12.91 | 6.1 |
| 2006 | 7.05 | 11.4 | 3.09 |
| 2005 | 2.93 | 4 | 1.99 |
| 2004 | 3.82 | 6.32 | 2.5 |