| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.65 | 0.83 | 0.53 |
| 2024 | 0.71 | 1.44 | 0.32 |
| 2023 | 1.63 | 2.31 | 1.22 |
| 2022 | 1.44 | 2.17 | 1.1 |
| 2021 | 1.52 | 1.87 | 1.27 |
| 2020 | 2 | 2.5 | 1.43 |
| 2019 | 1.69 | 2.12 | 1.28 |
| 2018 | 1.93 | 2.68 | 1.12 |
| 2017 | 2.93 | 3.5 | 2.43 |
| 2016 | 3.92 | 4.93 | 3.09 |
| 2015 | 6.48 | 15.32 | 3.12 |
| 2014 | 5.73 | 10.37 | 4.16 |
| 2013 | 6.02 | 7.58 | 4.21 |
| 2012 | 3.89 | 4.93 | 3.19 |
| 2011 | 5.54 | 7.73 | 4.26 |
| 2010 | 7.14 | 8.59 | 6.06 |