| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.62 | 2.26 | 1.22 |
| 2024 | 1.4 | 1.78 | 1.1 |
| 2023 | 1.79 | 2.22 | 1.45 |
| 2022 | 2.15 | 2.74 | 1.75 |
| 2021 | 1.24 | 2.33 | 0.65 |
| 2020 | 0.8 | 1.28 | 0.53 |
| 2019 | 5.94 | 15.46 | 0.89 |
| 2018 | 5.49 | 10.37 | 4.02 |
| 2017 | 9.24 | 12.71 | 6.87 |
| 2016 | 8.86 | 11.84 | 6.9 |
| 2015 | 3.78 | 7.3 | 1.25 |
| 2014 | 0.69 | 1.25 | 0.5 |
| 2013 | 0.91 | 1.21 | 0.64 |
| 2012 | 0.98 | 1.2 | 0.79 |
| 2011 | 1.46 | 2.08 | 1.01 |
| 2010 | 1.59 | 2.41 | 1.13 |
| 2009 | 1.37 | 2.21 | 0.75 |
| 2008 | 1.53 | 2.59 | 0.61 |
| 2007 | 1.95 | 3.21 | 1.13 |
| 2006 | 1.26 | 1.85 | 0.96 |
| 2005 | 1.05 | 1.33 | 0.74 |