| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.89 | 1.11 | 0.77 |
| 2024 | 0.77 | 0.93 | 0.58 |
| 2023 | 0.87 | 0.96 | 0.79 |
| 2022 | 0.94 | 1.33 | 0.73 |
| 2021 | 0.86 | 1.32 | 0.54 |
| 2020 | 0.69 | 0.87 | 0.58 |
| 2019 | 0.89 | 1.5 | 0.58 |
| 2018 | 0.84 | 1.21 | 0.56 |
| 2017 | 1.42 | 1.83 | 1.09 |
| 2016 | 18.07 | 64.11 | 1.4 |
| 2015 | 16.75 | 75.68 | 6.48 |
| 2014 | 6.1 | 7.99 | 5.24 |
| 2013 | 6.28 | 7.43 | 5.3 |
| 2012 | 7.47 | 9.61 | 5.74 |
| 2011 | 10.96 | 14.12 | 6.85 |
| 2010 | 10.33 | 13.39 | 7.4 |
| 2009 | 8.47 | 12.72 | 4.97 |
| 2008 | 8.97 | 17.26 | 3.5 |
| 2007 | 5.2 | 15.59 | 1.16 |
| 2006 | 1.01 | 1.32 | 0.58 |
| 2005 | 0.46 | 0.65 | 0.23 |
| 2004 | 0.46 | 0.79 | 0.28 |