| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.21 | 0.23 | 0.19 |
| 2024 | 0.22 | 0.29 | 0.17 |
| 2023 | 0.27 | 0.43 | 0.22 |
| 2022 | 0.22 | 0.29 | 0.18 |
| 2021 | 0.19 | 0.23 | 0.16 |
| 2020 | 0.26 | 0.38 | 0.2 |
| 2019 | 0.26 | 0.36 | 0.21 |
| 2018 | 0.27 | 0.37 | 0.2 |
| 2017 | 0.42 | 0.54 | 0.3 |
| 2016 | 0.47 | 0.62 | 0.4 |
| 2015 | 0.7 | 1.22 | 0.39 |
| 2014 | 0.32 | 0.5 | 0.26 |
| 2013 | 0.26 | 0.32 | 0.2 |
| 2012 | 0.27 | 0.31 | 0.23 |
| 2011 | 0.32 | 0.41 | 0.24 |
| 2010 | 0.5 | 0.73 | 0.35 |
| 2009 | 0.93 | 1.37 | 0.64 |
| 2008 | 1.05 | 1.84 | 0.47 |
| 2007 | 1.32 | 2.02 | 0.64 |
| 2006 | 0.56 | 0.75 | 0.41 |
| 2005 | 0.46 | 0.62 | 0.33 |
| 2004 | 0.72 | 1.29 | 0.39 |