| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.79 | 3.53 | 1.99 |
| 2024 | 2.8 | 4.31 | 1.71 |
| 2023 | 2.57 | 3.41 | 1.9 |
| 2022 | 2.32 | 3.39 | 1.91 |
| 2021 | 1.74 | 2.42 | 1.15 |
| 2020 | 1.82 | 2.94 | 1.26 |
| 2019 | 3.05 | 4.17 | 2.1 |
| 2018 | 3.52 | 5.3 | 1.91 |
| 2017 | 5.81 | 8.72 | 4.84 |
| 2016 | 6.19 | 10.27 | 4.39 |
| 2015 | 7.94 | 12.77 | 5.52 |
| 2014 | 3.74 | 7.71 | 2.41 |
| 2013 | 3.95 | 5.62 | 2.05 |
| 2012 | 4.95 | 6.33 | 4.06 |
| 2011 | 7.29 | 10.71 | 4.9 |
| 2010 | 9.61 | 13.6 | 6.59 |
| 2009 | 8.28 | 14.54 | 4.95 |
| 2008 | 6.41 | 11.98 | 3.12 |
| 2007 | 6.87 | 11.46 | 3.8 |
| 2006 | 3.2 | 4.63 | 1.84 |
| 2005 | 2.24 | 3.52 | 1.47 |
| 2004 | 4.84 | 6.91 | 3.15 |
| 2003 | 7.17 | 9 | 4.47 |
| 2002 | 9.6 | 11.73 | 6.45 |