| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.27 | 2.2 | 0.72 |
| 2024 | 0.71 | 0.91 | 0.49 |
| 2023 | 0.76 | 0.93 | 0.61 |
| 2022 | 0.88 | 1.12 | 0.73 |
| 2021 | 1.26 | 2.11 | 0.48 |
| 2020 | 0.5 | 0.71 | 0.42 |
| 2019 | 0.6 | 0.84 | 0.49 |
| 2018 | 0.67 | 0.88 | 0.49 |
| 2017 | 1.29 | 1.77 | 0.83 |
| 2016 | 1.5 | 1.85 | 1.29 |
| 2015 | 1.28 | 2.79 | 0.49 |
| 2014 | 0.34 | 0.55 | 0.28 |
| 2013 | 0.33 | 0.39 | 0.28 |
| 2012 | 0.26 | 0.34 | 0.18 |
| 2011 | 0.42 | 0.55 | 0.29 |
| 2010 | 0.67 | 1.29 | 0.38 |
| 2009 | 1.1 | 1.41 | 0.61 |
| 2008 | 1.02 | 1.95 | 0.5 |
| 2007 | 1.7 | 2.79 | 0.8 |
| 2006 | 0.81 | 1 | 0.72 |
| 2005 | 0.9 | 1.19 | 0.68 |
| 2004 | 1.82 | 2.7 | 1.18 |