| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0 | ||
| 2024 | 1.74 | 4 | 0.19 |
| 2023 | 4.81 | 6.26 | 2.56 |
| 2022 | 4.1 | 6.32 | 2.56 |
| 2021 | 4 | 5.09 | 3.16 |
| 2020 | 4.02 | 6.84 | 2.67 |
| 2019 | 5.56 | 8.51 | 3.51 |
| 2018 | 3.86 | 6.26 | 2.34 |
| 2017 | 3.07 | 4.01 | 2.36 |
| 2016 | 4.29 | 5.07 | 3 |
| 2015 | 5.69 | 10.67 | 2.63 |
| 2014 | 12.76 | 20.85 | 7.4 |
| 2013 | 8.71 | 12.28 | 5.28 |
| 2012 | 6.6 | 9.73 | 4.94 |