| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.73 | 1.8 | 1.68 |
| 2024 | 1.74 | 1.97 | 1.48 |
| 2023 | 2.02 | 2.79 | 1.73 |
| 2022 | 1.82 | 2.56 | 1.44 |
| 2021 | 2.23 | 2.58 | 2.01 |
| 2020 | 2.89 | 3.43 | 2.45 |
| 2019 | 3.38 | 5.08 | 2.59 |
| 2018 | 3.35 | 4.19 | 2.67 |
| 2017 | 3.94 | 4.39 | 3.68 |
| 2016 | 3.94 | 4.48 | 3.32 |
| 2015 | 6.57 | 10.7 | 3.78 |
| 2014 | 4.9 | 5.61 | 4.17 |
| 2013 | 4.97 | 6.86 | 3.79 |
| 2012 | 4.56 | 5.52 | 3.49 |
| 2011 | 5.4 | 7.29 | 3.51 |
| 2010 | 5.11 | 7.34 | 3.92 |
| 2009 | 3.16 | 4.69 | 2 |
| 2008 | 3.24 | 6.03 | 1.5 |
| 2007 | 4.66 | 7.83 | 2.2 |
| 2006 | 1.9 | 2.38 | 1.46 |
| 2005 | 1.67 | 1.93 | 1.31 |