| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.31 | 0.44 | 0.25 |
| 2024 | 0.26 | 0.39 | 0.2 |
| 2023 | 0.36 | 0.51 | 0.32 |
| 2022 | 0.37 | 0.45 | 0.3 |
| 2021 | 0.35 | 0.47 | 0.29 |
| 2020 | 0.42 | 0.52 | 0.36 |
| 2019 | 0.47 | 0.61 | 0.33 |
| 2018 | 0.47 | 0.71 | 0.25 |
| 2017 | 0.97 | 1.35 | 0.62 |
| 2016 | 0.97 | 1.4 | 0.66 |
| 2015 | 0.96 | 1.75 | 0.58 |
| 2014 | 0.64 | 0.92 | 0.5 |
| 2013 | 0.65 | 0.83 | 0.52 |
| 2012 | 0.77 | 0.98 | 0.58 |
| 2011 | 1.11 | 1.57 | 0.73 |
| 2010 | 1.26 | 1.79 | 0.91 |
| 2009 | 1.52 | 1.82 | 1.23 |
| 2008 | 1.71 | 2.81 | 1.03 |
| 2007 | 1.31 | 2.5 | 0.42 |
| 2006 | 0.38 | 0.48 | 0.25 |
| 2005 | 0.34 | 0.42 | 0.25 |
| 2004 | 0.45 | 0.79 | 0.28 |