| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.31 | 2.98 | 1.94 |
| 2024 | 1.87 | 2.7 | 1.39 |
| 2023 | 1.99 | 2.98 | 1.51 |
| 2022 | 1.55 | 2.06 | 1.15 |
| 2021 | 1.38 | 2.04 | 0.96 |
| 2020 | 1.04 | 1.54 | 0.64 |
| 2019 | 0.89 | 1.18 | 0.67 |
| 2018 | 1.4 | 1.94 | 0.88 |
| 2017 | 2.14 | 2.72 | 1.65 |
| 2016 | 6.97 | 22.08 | 2.14 |
| 2015 | 7.01 | 13.29 | 5.29 |
| 2014 | 4.2 | 5.74 | 3.1 |
| 2013 | 3.23 | 4.16 | 2.61 |
| 2012 | 4.03 | 5.01 | 2.79 |
| 2011 | 5.72 | 8.59 | 3.93 |
| 2010 | 4.66 | 5.91 | 3.56 |
| 2009 | 3.86 | 4.98 | 2.69 |
| 2008 | 3.08 | 4.98 | 1.59 |