| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.88 | 3.49 | 2.39 |
| 2024 | 2.17 | 3.18 | 1.68 |
| 2023 | 2.87 | 3.7 | 2.57 |
| 2022 | 2.56 | 3.52 | 2.05 |
| 2021 | 2.37 | 3.92 | 1.98 |
| 2020 | 2.4 | 3.1 | 1.67 |
| 2019 | 2.1 | 2.77 | 1.69 |
| 2018 | 2.35 | 3.08 | 1.6 |
| 2017 | 2.74 | 3.18 | 2.08 |
| 2016 | 4.2 | 8.86 | 2.52 |
| 2015 | 8.69 | 18.07 | 5.58 |
| 2014 | 6.99 | 8.68 | 5.26 |
| 2013 | 4.58 | 5.58 | 3.5 |
| 2012 | 6.75 | 9.51 | 4.5 |
| 2011 | 10.57 | 13.56 | 8.22 |
| 2010 | 11.65 | 17.22 | 6.61 |