| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.39 | 2.06 | 0.93 |
| 2024 | 0.8 | 1.33 | 0.35 |
| 2023 | 0.88 | 1.63 | 0.47 |
| 2022 | 1.47 | 1.91 | 1 |
| 2021 | 1.57 | 2.17 | 0.9 |
| 2020 | 1.91 | 2.33 | 1.48 |
| 2019 | 1.4 | 1.77 | 1.08 |
| 2018 | 1.71 | 3.14 | 1.05 |
| 2017 | 4.31 | 6.32 | 2.63 |
| 2016 | 3.62 | 5.73 | 2.01 |
| 2015 | 3.56 | 7.67 | 1.63 |
| 2014 | 3.01 | 5.12 | 2.2 |
| 2013 | 2.86 | 3.31 | 2.35 |
| 2012 | 2.86 | 4.17 | 1.64 |
| 2011 | 2.02 | 2.86 | 1.27 |
| 2010 | 4.92 | 8.1 | 2.64 |
| 2009 | 3.75 | 7.29 | 1.39 |
| 2008 | 2.97 | 11.32 | 0.96 |
| 2007 | 13.71 | 26.11 | 4.41 |
| 2006 | 2.5 | 4.41 | 1.49 |
| 2005 | 1.26 | 1.89 | 0.72 |
| 2004 | 1.82 | 3.28 | 0.93 |