| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 4.02 | 4.38 | 3.77 |
| 2024 | 3.93 | 4.52 | 3.15 |
| 2023 | 3.5 | 4.18 | 3.04 |
| 2022 | 3.51 | 4.36 | 2.24 |
| 2021 | 3.06 | 5.22 | 1.99 |
| 2020 | 2.43 | 3.32 | 1.66 |
| 2019 | 1.7 | 2.32 | 1.48 |
| 2018 | 2.49 | 3.39 | 1.59 |
| 2017 | 2.75 | 3.16 | 2.29 |
| 2016 | 2.04 | 2.42 | 1.81 |
| 2015 | 2.69 | 4.18 | 1.64 |
| 2014 | 2.05 | 2.41 | 1.7 |
| 2013 | 2.28 | 2.88 | 1.79 |
| 2012 | 2.72 | 3.46 | 2.18 |
| 2011 | 4.1 | 6.23 | 2.89 |
| 2010 | 6.37 | 8.16 | 4.91 |
| 2009 | 6.07 | 7.28 | 5 |
| 2008 | 6.33 | 11.08 | 3.31 |
| 2007 | 7.64 | 11.71 | 4.45 |
| 2006 | 3.6 | 4.58 | 2.54 |
| 2005 | 4.19 | 8.57 | 2.74 |