| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.56 | 2.96 | 2.18 |
| 2024 | 2.56 | 3.68 | 1.83 |
| 2023 | 3.61 | 5.71 | 2.7 |
| 2022 | 3.69 | 5.57 | 2.39 |
| 2021 | 4.13 | 6.42 | 3.4 |
| 2020 | 5.49 | 11.56 | 3.71 |
| 2019 | 7.75 | 11.72 | 4.32 |
| 2018 | 4.9 | 6.52 | 3.45 |
| 2017 | 8.94 | 13.69 | 5.47 |
| 2016 | 6.2 | 10.91 | 4.15 |
| 2015 | 4.6 | 7.57 | 2.89 |
| 2014 | 3.76 | 6 | 2.59 |
| 2013 | 4.71 | 6.21 | 3.51 |
| 2012 | 4.44 | 9.17 | 3.05 |
| 2011 | 7.68 | 9.22 | 6.2 |
| 2010 | 14.59 | 24.23 | 7.41 |
| 2009 | 19.17 | 30.49 | 5.93 |
| 2008 | 12.58 | 40.72 | 4.34 |
| 2007 | 44.77 | 82.38 | 7.39 |
| 2006 | 5.53 | 6.93 | 3.35 |
| 2005 | 3.65 | 5.61 | 2.28 |
| 2004 | 7.16 | 16.41 | 4.68 |