| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.24 | 2.63 | 1.78 |
| 2024 | 2.41 | 4.57 | 1.51 |
| 2023 | 1.23 | 3.3 | 0.63 |
| 2022 | 0.71 | 1.07 | 0.48 |
| 2021 | 0.54 | 0.69 | 0.4 |
| 2020 | 0.81 | 1.55 | 0.51 |
| 2019 | 2.94 | 5.39 | 1.39 |
| 2018 | 4.57 | 5.38 | 3.54 |
| 2017 | 3.77 | 5.37 | 2.49 |
| 2016 | 2.34 | 3.09 | 1.77 |
| 2015 | 2.01 | 4.03 | 0.85 |
| 2014 | 0.82 | 1.3 | 0.6 |
| 2013 | 0.96 | 1.2 | 0.78 |
| 2012 | 1.08 | 1.32 | 0.79 |
| 2011 | 1.82 | 1.96 | 0.91 |
| 2010 | 2.2 | 3.26 | 1.61 |
| 2009 | 1.75 | 3.11 | 0.8 |
| 2008 | 2.65 | 5.68 | 0.43 |
| 2007 | 3.73 | 7.94 | 0.84 |
| 2006 | 1.27 | 1.93 | 0.83 |
| 2005 | 1.08 | 1.42 | 0.7 |
| 2004 | 1.23 | 1.86 | 0.83 |