| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.78 | 1.05 | 0.61 |
| 2024 | 0.52 | 0.81 | 0.37 |
| 2023 | 0.51 | 0.63 | 0.46 |
| 2022 | 0.58 | 0.91 | 0.44 |
| 2021 | 0.78 | 1.36 | 0.44 |
| 2020 | 0.52 | 0.71 | 0.39 |
| 2019 | 0.5 | 0.65 | 0.43 |
| 2018 | 0.61 | 0.98 | 0.47 |
| 2017 | 1.05 | 1.89 | 0.7 |
| 2016 | 1.09 | 1.33 | 0.92 |
| 2015 | 1.3 | 2.59 | 0.69 |
| 2014 | 0.46 | 0.77 | 0.3 |
| 2013 | 0.37 | 0.44 | 0.3 |
| 2012 | 0.43 | 0.55 | 0.33 |
| 2011 | 0.41 | 0.55 | 0.3 |
| 2010 | 0.53 | 0.8 | 0.39 |
| 2009 | 0.47 | 0.84 | 0.21 |
| 2008 | 0.28 | 0.47 | 0.14 |
| 2007 | 0.37 | 0.53 | 0.24 |
| 2006 | 0.3 | 0.44 | 0.22 |
| 2005 | 0.43 | 0.62 | 0.33 |
| 2004 | 0.93 | 1.77 | 0.43 |