| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2026 | 0.63 | 0.71 | 0.56 |
| 2025 | 0.47 | 0.8 | 0.31 |
| 2024 | 0.36 | 0.45 | 0.28 |
| 2023 | 0.45 | 0.52 | 0.41 |
| 2022 | 0.52 | 0.81 | 0.42 |
| 2021 | 0.59 | 0.86 | 0.42 |
| 2020 | 0.79 | 1.32 | 0.48 |
| 2019 | 0.57 | 0.73 | 0.46 |
| 2018 | 0.6 | 1.12 | 0.32 |
| 2017 | 7.16 | 17.28 | 0.68 |
| 2016 | 15.25 | 18.96 | 10.59 |
| 2015 | 18.52 | 39.15 | 11.15 |
| 2014 | 9.38 | 14.16 | 6.37 |
| 2013 | 6.94 | 8 | 5.99 |
| 2012 | 5.73 | 6.73 | 4.42 |
| 2011 | 4.71 | 7.87 | 2.61 |
| 2010 | 10.91 | 29.97 | 2.58 |
| 2009 | 28.46 | 42.48 | 20.88 |
| 2008 | 33.25 | 59.59 | 9.29 |
| 2007 | 12.62 | 37.01 | 2.9 |
| 2006 | 22.3 | 39.47 | 2.16 |
| 2005 | 14.48 | 22.9 | 3.88 |
| 2004 | 6.02 | 9.09 | 3.92 |