| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.95 | 1.17 | 0.9 |
| 2024 | 0.85 | 1.05 | 0.7 |
| 2023 | 0.94 | 1.13 | 0.79 |
| 2022 | 1.2 | 1.79 | 0.85 |
| 2021 | 2.35 | 5.54 | 0.63 |
| 2020 | 0.65 | 0.8 | 0.56 |
| 2019 | 0.79 | 1.07 | 0.63 |
| 2018 | 0.62 | 0.8 | 0.46 |
| 2017 | 1.01 | 1.26 | 0.76 |
| 2016 | 1.19 | 1.38 | 0.92 |
| 2015 | 1.19 | 1.74 | 0.85 |
| 2014 | 0.57 | 1.09 | 0.42 |
| 2013 | 0.45 | 0.54 | 0.33 |
| 2012 | 0.27 | 0.33 | 0.21 |
| 2011 | 0.41 | 0.57 | 0.22 |
| 2010 | 0.56 | 0.83 | 0.4 |
| 2009 | 0.58 | 0.77 | 0.33 |
| 2008 | 0.6 | 1.29 | 0.23 |
| 2007 | 0.93 | 1.31 | 0.49 |
| 2006 | 0.5 | 0.7 | 0.39 |
| 2005 | 0.78 | 1.46 | 0.41 |
| 2004 | 1.69 | 3 | 0.97 |