| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.53 | 0.58 | 0.48 |
| 2024 | 0.63 | 0.79 | 0.5 |
| 2023 | 0.7 | 0.98 | 0.49 |
| 2022 | 0.57 | 0.78 | 0.44 |
| 2021 | 0.72 | 0.97 | 0.5 |
| 2020 | 0.48 | 0.59 | 0.39 |
| 2019 | 0.52 | 0.71 | 0.43 |
| 2018 | 0.65 | 1.01 | 0.44 |
| 2017 | 0.78 | 1.04 | 0.57 |
| 2016 | 0.55 | 0.7 | 0.48 |
| 2015 | 0.68 | 1.04 | 0.42 |
| 2014 | 0.43 | 0.64 | 0.35 |
| 2013 | 0.52 | 0.65 | 0.41 |
| 2012 | 0.53 | 0.76 | 0.34 |
| 2011 | 1.09 | 1.68 | 0.57 |
| 2010 | 1 | 1.4 | 0.69 |
| 2009 | 0.83 | 1.09 | 0.41 |
| 2008 | 0.75 | 1.2 | 0.33 |
| 2007 | 0.96 | 1.31 | 0.64 |
| 2006 | 0.82 | 1.2 | 0.6 |