| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.34 | 0.38 | 0.3 |
| 2024 | 0.31 | 0.34 | 0.25 |
| 2023 | 0.36 | 0.43 | 0.3 |
| 2022 | 0.46 | 0.66 | 0.34 |
| 2021 | 0.58 | 0.79 | 0.42 |
| 2020 | 0.58 | 0.88 | 0.41 |
| 2019 | 0.47 | 0.58 | 0.35 |
| 2018 | 0.49 | 0.67 | 0.34 |
| 2017 | 0.52 | 0.69 | 0.4 |
| 2016 | 0.47 | 0.58 | 0.41 |
| 2015 | 0.61 | 0.86 | 0.4 |
| 2014 | 0.41 | 0.58 | 0.33 |
| 2013 | 0.4 | 0.5 | 0.31 |
| 2012 | 0.46 | 0.54 | 0.39 |
| 2011 | 0.61 | 0.82 | 0.41 |
| 2010 | 0.95 | 1.72 | 0.59 |
| 2009 | 2.64 | 4.8 | 0.83 |
| 2008 | 1.67 | 2.85 | 0.64 |
| 2007 | 2.31 | 4.13 | 0.8 |
| 2006 | 0.66 | 0.81 | 0.52 |
| 2005 | 0.65 | 0.82 | 0.48 |
| 2004 | 0.75 | 1.26 | 0.54 |