| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.59 | 3.11 | 2.25 |
| 2024 | 1.77 | 3 | 1.32 |
| 2023 | 1.84 | 2.59 | 1.38 |
| 2022 | 1.58 | 2.15 | 1.28 |
| 2021 | 1.4 | 1.92 | 1.06 |
| 2020 | 1.52 | 2.02 | 1.09 |
| 2019 | 1.66 | 2.17 | 1.29 |
| 2018 | 2.04 | 4.13 | 1.01 |
| 2017 | 5.39 | 6.84 | 3.62 |
| 2016 | 3.94 | 6.26 | 2.75 |
| 2015 | 4.18 | 8.47 | 2.09 |
| 2014 | 3.24 | 5.07 | 2.24 |
| 2013 | 2.41 | 3.04 | 1.91 |
| 2012 | 2.17 | 2.91 | 1.68 |
| 2011 | 4.71 | 6.45 | 2.31 |
| 2010 | 5.72 | 9.8 | 3.17 |
| 2009 | 23.35 | 55.39 | 7.92 |
| 2008 | 15.41 | 19.16 | 11.68 |
| 2007 | 14.56 | 34.28 | 8.64 |
| 2006 | 4.9 | 10.05 | 1.73 |
| 2005 | 2.73 | 3.53 | 1.49 |
| 2004 | 5.33 | 10.83 | 3.13 |