| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0 | ||
| 2024 | 0 | ||
| 2023 | 0 | ||
| 2022 | 0.21 | 0.21 | 0.21 |
| 2021 | 0.25 | 0.37 | 0.21 |
| 2020 | 0.3 | 0.5 | 0.2 |
| 2019 | 0.57 | 0.69 | 0.45 |
| 2018 | 0.6 | 0.69 | 0.51 |
| 2017 | 0.6 | 0.77 | 0.53 |
| 2016 | 0.68 | 0.85 | 0.59 |
| 2015 | 0.68 | 0.92 | 0.46 |
| 2014 | 0.61 | 0.79 | 0.51 |
| 2013 | 0.62 | 0.8 | 0.53 |
| 2012 | 0.83 | 0.99 | 0.71 |
| 2011 | 0.96 | 1.31 | 0.73 |
| 2010 | 1.8 | 3.02 | 1.28 |
| 2009 | 7.63 | 16.17 | 2.2 |