| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 3 | 4.53 | 2.17 |
| 2024 | 2.73 | 3.25 | 1.95 |
| 2023 | 3.42 | 5.33 | 2.45 |
| 2022 | 4.59 | 6.46 | 3.15 |
| 2021 | 5.05 | 7.54 | 3.81 |
| 2020 | 7.29 | 11.32 | 4.07 |
| 2019 | 3.68 | 4.92 | 2.33 |
| 2018 | 5.35 | 7.68 | 2.59 |
| 2017 | 5.35 | 6.77 | 4.5 |
| 2016 | 6.41 | 7.24 | 5.33 |
| 2015 | 6.24 | 9.16 | 4.62 |
| 2014 | 4.36 | 5.26 | 3.5 |
| 2013 | 5.02 | 7.2 | 3.32 |
| 2012 | 3.87 | 4.76 | 2.82 |
| 2011 | 5.8 | 7.92 | 3.31 |
| 2010 | 8.4 | 10.69 | 5.66 |
| 2009 | 5.69 | 9.27 | 4.56 |
| 2008 | 6.48 | 10.03 | 3.58 |
| 2007 | 8.2 | 11.36 | 6.1 |
| 2006 | 5.73 | 6.53 | 5.03 |
| 2005 | 7.09 | 8.97 | 4.85 |
| 2004 | 6.52 | 9.83 | 3.94 |