| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 4.3 | 5.52 | 3.35 |
| 2024 | 2.9 | 4.49 | 1.76 |
| 2023 | 3.16 | 3.69 | 2.34 |
| 2022 | 4.15 | 6.48 | 2.64 |
| 2021 | 4.55 | 6.76 | 2.97 |
| 2020 | 4.77 | 6.81 | 3.68 |
| 2019 | 3.78 | 6.13 | 2.31 |
| 2018 | 3.77 | 5.68 | 2.24 |
| 2017 | 6.35 | 7.82 | 5.16 |
| 2016 | 12.15 | 23.45 | 7.04 |
| 2015 | 7.91 | 27.8 | 3.66 |
| 2014 | 5.34 | 8.11 | 4.33 |
| 2013 | 5.04 | 6.72 | 3.81 |
| 2012 | 7.92 | 10.51 | 4.59 |
| 2011 | 9.74 | 12.28 | 7.38 |
| 2010 | 6.73 | 9.98 | 4.44 |
| 2009 | 3.89 | 5.3 | 2.55 |
| 2008 | 4.23 | 9.04 | 1.63 |
| 2007 | 8.38 | 13.28 | 2.84 |
| 2006 | 2.37 | 3.24 | 1.4 |
| 2005 | 1.66 | 2.05 | 1.27 |