| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.24 | 1.54 | 1.13 |
| 2024 | 1.02 | 2.18 | 0.74 |
| 2023 | 1.14 | 1.62 | 0.72 |
| 2022 | 0.72 | 0.86 | 0.56 |
| 2021 | 0.56 | 0.98 | 0.41 |
| 2020 | 0.43 | 0.56 | 0.34 |
| 2019 | 0.36 | 0.44 | 0.32 |
| 2018 | 0.39 | 0.47 | 0.31 |
| 2017 | 0.54 | 0.66 | 0.46 |
| 2016 | 0.56 | 0.66 | 0.43 |
| 2015 | 0.64 | 1.18 | 0.41 |
| 2014 | 0.35 | 0.53 | 0.26 |
| 2013 | 0.31 | 0.4 | 0.24 |
| 2012 | 0.43 | 0.61 | 0.27 |
| 2011 | 0.78 | 1.09 | 0.52 |
| 2010 | 0.98 | 1.29 | 0.76 |
| 2009 | 0.68 | 0.93 | 0.47 |
| 2008 | 0.98 | 1.62 | 0.44 |
| 2007 | 1.22 | 1.55 | 0.83 |
| 2006 | 0.71 | 1.03 | 0.48 |
| 2005 | 0.37 | 0.52 | 0.21 |
| 2004 | 0.41 | 0.76 | 0.25 |