| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.74 | 1.02 | 0.57 |
| 2024 | 0.84 | 1.01 | 0.67 |
| 2023 | 0.7 | 0.94 | 0.56 |
| 2022 | 0.65 | 0.86 | 0.42 |
| 2021 | 0.44 | 0.86 | 0.32 |
| 2020 | 0.6 | 0.88 | 0.41 |
| 2019 | 0.3 | 0.41 | 0.17 |
| 2018 | 0.19 | 0.22 | 0.17 |
| 2017 | 0.21 | 0.28 | 0.15 |
| 2016 | 0.19 | 0.25 | 0.14 |
| 2015 | 0.2 | 0.35 | 0.14 |
| 2014 | 0.12 | 0.21 | 0.07 |
| 2013 | 0.14 | 0.22 | 0.11 |
| 2012 | 0.31 | 0.52 | 0.14 |
| 2011 | 0.5 | 0.66 | 0.34 |
| 2010 | 2.05 | 9.55 | 0.42 |
| 2009 | 2.39 | 9.33 | 0.75 |
| 2008 | 0.96 | 2.08 | 0.47 |
| 2007 | 1.82 | 2.71 | 0.77 |
| 2006 | 0.67 | 1.05 | 0.42 |
| 2005 | 0.44 | 0.6 | 0.29 |
| 2004 | 0.56 | 0.9 | 0.35 |