| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.88 | 0.97 | 0.77 |
| 2024 | 0.62 | 1.15 | 0.41 |
| 2023 | 0.52 | 0.58 | 0.45 |
| 2022 | 0.57 | 0.88 | 0.43 |
| 2021 | 1.2 | 1.84 | 0.67 |
| 2020 | 1.86 | 2.64 | 0.85 |
| 2019 | 1.23 | 1.77 | 0.97 |
| 2018 | 2.64 | 3.16 | 1.22 |
| 2017 | 4.25 | 6.15 | 3.16 |
| 2016 | 4.56 | 6.15 | 1.91 |
| 2015 | 4.02 | 5.74 | 0.71 |
| 2014 | 0.61 | 0.86 | 0.43 |
| 2013 | 0.45 | 0.58 | 0.34 |
| 2012 | 0.42 | 0.57 | 0.26 |
| 2011 | 0.66 | 1.47 | 0.26 |
| 2010 | 65.76 | 73.46 | 59.41 |
| 2009 | 17.08 | 80.79 | 0.64 |
| 2008 | 0.77 | 1.7 | 0.26 |
| 2007 | 1.69 | 2.72 | 1.13 |