| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 4.33 | 6.02 | 3.47 |
| 2024 | 3.65 | 5.21 | 2.75 |
| 2023 | 4.91 | 5.68 | 4.23 |
| 2022 | 4.33 | 6.11 | 3.52 |
| 2021 | 4.08 | 4.77 | 3.56 |
| 2020 | 4.37 | 5.1 | 3.68 |
| 2019 | 5.5 | 7.49 | 3.78 |
| 2018 | 6.07 | 6.67 | 5.49 |
| 2017 | 7.62 | 9.2 | 6.34 |
| 2016 | 8.29 | 10 | 6.7 |
| 2015 | 7.07 | 10.61 | 3.31 |
| 2014 | 3.52 | 5.22 | 2.31 |
| 2013 | 3 | 4.76 | 2.34 |
| 2012 | 3.08 | 3.66 | 2.48 |
| 2011 | 3.73 | 4.49 | 3 |
| 2010 | 3.63 | 4.44 | 2.77 |
| 2009 | 2.92 | 3.96 | 2.25 |
| 2008 | 3.81 | 6.32 | 1.72 |
| 2007 | 4.22 | 6.88 | 2.09 |
| 2006 | 2.23 | 3.15 | 1.59 |
| 2005 | 1.56 | 2.38 | 0.95 |