| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.63 | 1.76 | 1.48 |
| 2024 | 1.59 | 2.03 | 1.18 |
| 2023 | 1.56 | 1.85 | 1.29 |
| 2022 | 1.48 | 1.7 | 1.22 |
| 2021 | 1.98 | 2.57 | 1.48 |
| 2020 | 3.3 | 4.28 | 2.57 |
| 2019 | 3.87 | 5.7 | 3.03 |
| 2018 | 5.98 | 10.34 | 3.03 |
| 2017 | 7.59 | 9.35 | 5.69 |
| 2016 | 5.15 | 6.71 | 3.26 |
| 2015 | 3.81 | 5.81 | 2.42 |
| 2014 | 3.08 | 3.71 | 2.58 |
| 2013 | 3.41 | 5.03 | 2.49 |
| 2012 | 3.4 | 4.54 | 2.79 |
| 2011 | 5.91 | 8.57 | 3.71 |
| 2010 | 5.94 | 9.18 | 4.22 |
| 2009 | 3.57 | 5.57 | 2.51 |
| 2008 | 4.32 | 7.9 | 1.43 |
| 2007 | 4.18 | 5.59 | 2.46 |
| 2006 | 2.07 | 2.73 | 1.59 |
| 2005 | 1.96 | 2.44 | 1.47 |