| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.45 | 1.63 | 1.17 |
| 2024 | 1.6 | 2.3 | 1.02 |
| 2023 | 2 | 2.32 | 1.59 |
| 2022 | 2.63 | 4.76 | 1.38 |
| 2021 | 2.71 | 4.02 | 2.15 |
| 2020 | 3.22 | 4.82 | 1.81 |
| 2019 | 2.07 | 3.07 | 1.62 |
| 2018 | 2.95 | 4.22 | 1.67 |
| 2017 | 5.45 | 6.84 | 4.01 |
| 2016 | 7.74 | 9.24 | 5.62 |
| 2015 | 10.11 | 23.57 | 3.42 |
| 2014 | 3.53 | 4.47 | 2.68 |
| 2013 | 3.41 | 4.73 | 2.12 |
| 2012 | 2.77 | 4.01 | 1.72 |
| 2011 | 6.52 | 13.98 | 3.46 |
| 2010 | 8.41 | 14.91 | 5.44 |
| 2009 | 4.13 | 6.78 | 2.2 |
| 2008 | 3.89 | 7.82 | 1.5 |
| 2007 | 5.99 | 8.11 | 4.57 |