| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.69 | 2.01 | 1.52 |
| 2024 | 1.46 | 2.42 | 0.87 |
| 2023 | 2.09 | 2.29 | 1.83 |
| 2022 | 2.32 | 2.75 | 2.02 |
| 2021 | 2.61 | 3.5 | 2.21 |
| 2020 | 2.5 | 3.22 | 1.87 |
| 2019 | 2.22 | 3.13 | 1.64 |
| 2018 | 4.43 | 8.78 | 2 |
| 2017 | 5.44 | 8.78 | 3.83 |
| 2016 | 2.54 | 4.77 | 1.45 |
| 2015 | 2.02 | 4.45 | 1.19 |
| 2014 | 0.75 | 1.81 | 0.48 |
| 2013 | 0.82 | 1.58 | 0.51 |
| 2012 | 1.88 | 2.64 | 1.32 |
| 2011 | 3.99 | 6.47 | 2.05 |
| 2010 | 4.94 | 6.21 | 3.59 |
| 2009 | 3.19 | 4.3 | 1.59 |
| 2008 | 3.1 | 5.57 | 1.41 |
| 2007 | 3.56 | 4.95 | 1.96 |
| 2006 | 1.72 | 2.22 | 1.35 |
| 2005 | 1.52 | 2.05 | 1.1 |
| 2004 | 1.84 | 2.89 | 1.19 |