| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2024 | 2.81 | 3.28 | 2.38 |
| 2023 | 3.6 | 4.53 | 2.75 |
| 2022 | 3.94 | 5.05 | 3.31 |
| 2021 | 6.51 | 10.29 | 4.66 |
| 2020 | 4.52 | 6.57 | 2.99 |
| 2019 | 3.52 | 4.91 | 1.6 |
| 2018 | 3.84 | 5.45 | 2.31 |
| 2017 | 4.24 | 5.66 | 3.1 |
| 2016 | 3.15 | 3.71 | 2.45 |
| 2015 | 4.28 | 5.71 | 3.11 |
| 2014 | 3.84 | 4.82 | 2.97 |
| 2013 | 4.41 | 5.12 | 3.61 |
| 2012 | 4.05 | 4.75 | 3.57 |
| 2011 | 5.7 | 7.93 | 3.62 |
| 2010 | 6.28 | 8.82 | 4.16 |
| 2009 | 6.39 | 8.41 | 3.89 |
| 2008 | 9.83 | 20.08 | 2.94 |
| 2007 | 19.04 | 24.2 | 13.41 |
| 2006 | 8.73 | 12.9 | 7.03 |
| 2005 | 7.36 | 12.35 | 5.77 |
| 2004 | 6.74 | 8.03 | 3.58 |
| 2003 | 5.87 | 6.67 | 5.02 |
| 2002 | 6.68 | 9.49 | 4.82 |