| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 3.04 | 3.28 | 2.71 |
| 2024 | 2.9 | 3.68 | 2.34 |
| 2023 | 3.44 | 5.85 | 2.38 |
| 2022 | 3.71 | 5.5 | 2.5 |
| 2021 | 4.42 | 5.62 | 3.41 |
| 2020 | 4.48 | 6.89 | 3.2 |
| 2019 | 2.76 | 3.54 | 2.3 |
| 2018 | 3.95 | 6.02 | 2.39 |
| 2017 | 6.79 | 8.62 | 4.74 |
| 2016 | 6.74 | 8.58 | 4.65 |
| 2015 | 6.8 | 10.89 | 3.14 |
| 2014 | 2.82 | 4.23 | 2.13 |
| 2013 | 2.49 | 3.21 | 2.01 |
| 2012 | 2.39 | 3.09 | 1.91 |
| 2011 | 4.04 | 5.44 | 2.06 |
| 2010 | 3.81 | 5.25 | 3 |
| 2009 | 2.64 | 3.29 | 1.73 |
| 2008 | 2.5 | 4.3 | 1.28 |
| 2007 | 3.1 | 3.94 | 1.88 |
| 2006 | 1.86 | 2.28 | 1.48 |