| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.85 | 1.09 | 0.68 |
| 2024 | 0.66 | 1.42 | 0.46 |
| 2023 | 0.88 | 1.2 | 0.69 |
| 2022 | 1.2 | 1.52 | 1 |
| 2021 | 1.9 | 3.44 | 1.24 |
| 2020 | 32.64 | 52.97 | 2.46 |
| 2019 | 28.64 | 39.8 | 18.87 |
| 2018 | 23.24 | 30.88 | 19.65 |
| 2017 | 39.44 | 53.23 | 28.15 |
| 2016 | 36.25 | 46.31 | 23.79 |
| 2015 | 40.87 | 93.84 | 23.57 |
| 2014 | 22.68 | 29.47 | 17.22 |
| 2013 | 24.26 | 30.27 | 20.55 |
| 2012 | 11.58 | 24.49 | 6.1 |
| 2011 | 16.49 | 21.88 | 8.71 |
| 2010 | 18.55 | 23.36 | 13.85 |
| 2009 | 15.19 | 23.61 | 9.32 |
| 2008 | 19.34 | 50.22 | 5.03 |
| 2007 | 32.77 | 46.06 | 16.07 |
| 2006 | 10.67 | 18.39 | 7.29 |
| 2005 | 6.42 | 10.67 | 2.58 |
| 2004 | 5.63 | 10.57 | 3.6 |