| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.05 | 2.48 | 1.49 |
| 2024 | 1.04 | 2.99 | 0.68 |
| 2023 | 1.2 | 1.53 | 1 |
| 2022 | 1.11 | 1.4 | 0.86 |
| 2021 | 1.48 | 1.95 | 1.1 |
| 2020 | 2.79 | 3.94 | 1.78 |
| 2019 | 1.55 | 2.47 | 0.94 |
| 2018 | 1.53 | 2.26 | 1.02 |
| 2017 | 2.59 | 3.46 | 1.89 |
| 2016 | 6.55 | 13.23 | 3.42 |
| 2015 | 8.82 | 18.04 | 5.28 |
| 2014 | 5 | 6.27 | 4.07 |
| 2013 | 3 | 4.16 | 2.34 |
| 2012 | 3.62 | 6.25 | 2.3 |
| 2011 | 7.7 | 11.7 | 4.89 |
| 2010 | 6.79 | 8.38 | 5.26 |
| 2009 | 4.62 | 6.08 | 2.36 |
| 2008 | 3.18 | 5.56 | 1.59 |