| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2024 | 0.61 | 0.79 | 0.46 |
| 2023 | 0.58 | 0.66 | 0.5 |
| 2022 | 0.56 | 0.73 | 0.44 |
| 2021 | 0.73 | 1.04 | 0.57 |
| 2020 | 0.68 | 0.81 | 0.54 |
| 2019 | 0.57 | 0.75 | 0.38 |
| 2018 | 0.43 | 0.52 | 0.37 |
| 2017 | 0.49 | 0.58 | 0.38 |
| 2016 | 0.44 | 0.54 | 0.36 |
| 2015 | 0.65 | 0.91 | 0.41 |
| 2014 | 0.63 | 0.78 | 0.55 |
| 2013 | 0.84 | 1.15 | 0.66 |
| 2012 | 0.86 | 1.05 | 0.61 |
| 2011 | 1.19 | 1.79 | 0.79 |
| 2010 | 1.5 | 2.09 | 1.03 |
| 2009 | 1.11 | 1.81 | 0.44 |
| 2008 | 0.58 | 1.07 | 0.32 |