| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.6 | 1.81 | 1.41 |
| 2024 | 1.4 | 2.64 | 0.95 |
| 2023 | 1.66 | 1.96 | 1.43 |
| 2022 | 1.65 | 2.12 | 1.18 |
| 2021 | 2.03 | 3.27 | 1.42 |
| 2020 | 1.59 | 2.92 | 1.01 |
| 2019 | 1.76 | 2.52 | 1.2 |
| 2018 | 3.06 | 5.41 | 1.65 |
| 2017 | 4.6 | 6.36 | 3.43 |
| 2016 | 4.78 | 6.42 | 3.95 |
| 2015 | 10.94 | 25.04 | 4.58 |
| 2014 | 4.72 | 7.4 | 3.27 |
| 2013 | 3.31 | 4.98 | 2.52 |
| 2012 | 3.12 | 4 | 2.43 |
| 2011 | 4.53 | 6.5 | 2.55 |
| 2010 | 6.65 | 8 | 5.58 |