| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.99 | 1.07 | 0.9 |
| 2024 | 0.84 | 1.46 | 0.59 |
| 2023 | 1.35 | 2.47 | 0.67 |
| 2022 | 2.94 | 3.93 | 2.21 |
| 2021 | 4.06 | 5.91 | 3.03 |
| 2020 | 2.27 | 4.43 | 1.38 |
| 2019 | 1.71 | 2.26 | 1.11 |
| 2018 | 1.28 | 2.05 | 0.71 |
| 2017 | 1.32 | 2.22 | 0.88 |
| 2016 | 1.03 | 1.42 | 0.63 |
| 2015 | 0.69 | 1.24 | 0.49 |
| 2014 | 0.51 | 0.56 | 0.43 |
| 2013 | 0.34 | 0.5 | 0.26 |
| 2012 | 0.33 | 0.44 | 0.27 |
| 2011 | 0.55 | 0.72 | 0.3 |
| 2010 | 0.67 | 0.86 | 0.48 |
| 2009 | 0.64 | 0.81 | 0.51 |
| 2008 | 1.25 | 2.68 | 0.32 |
| 2007 | 1.63 | 2.49 | 1.03 |
| 2006 | 0.72 | 1.08 | 0.56 |
| 2005 | 0.54 | 0.62 | 0.45 |