| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.94 | 2.62 | 1.51 |
| 2024 | 1.35 | 2.47 | 1.05 |
| 2023 | 1.92 | 2.37 | 1.54 |
| 2022 | 2.2 | 2.77 | 1.8 |
| 2021 | 3.55 | 4.92 | 2.48 |
| 2020 | 7.6 | 15.38 | 4.42 |
| 2019 | 1.31 | 16.49 | 0.4 |
| 2018 | 0.52 | 0.68 | 0.39 |
| 2017 | 0.73 | 0.9 | 0.61 |
| 2016 | 0.76 | 0.96 | 0.5 |
| 2015 | 0.67 | 1.29 | 0.43 |
| 2014 | 0.41 | 0.55 | 0.31 |
| 2013 | 0.36 | 0.44 | 0.3 |
| 2012 | 0.41 | 0.5 | 0.31 |
| 2011 | 0.69 | 0.82 | 0.37 |
| 2010 | 0.77 | 0.96 | 0.55 |
| 2009 | 0.66 | 0.92 | 0.37 |
| 2008 | 0.53 | 1 | 0.25 |
| 2007 | 0.83 | 1.32 | 0.35 |
| 2006 | 0.4 | 0.48 | 0.32 |
| 2005 | 0.35 | 0.45 | 0.23 |
| 2004 | 0.38 | 0.82 | 0.23 |