| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.82 | 3.18 | 2.42 |
| 2024 | 2.45 | 4.41 | 1.65 |
| 2023 | 2.37 | 3.47 | 1.69 |
| 2022 | 1.6 | 1.83 | 1.17 |
| 2021 | 1.32 | 1.87 | 0.89 |
| 2020 | 1.26 | 1.64 | 0.99 |
| 2019 | 1.07 | 1.48 | 0.79 |
| 2018 | 1.01 | 1.58 | 0.56 |
| 2017 | 2.18 | 2.86 | 1.51 |
| 2016 | 3.73 | 6.25 | 2.73 |
| 2015 | 8.67 | 11.2 | 4.38 |
| 2014 | 4.44 | 5.15 | 3.84 |
| 2013 | 3.16 | 4.82 | 2.57 |
| 2012 | 3.19 | 4.09 | 2.19 |
| 2011 | 2.22 | 3.46 | 1.71 |
| 2010 | 1.78 | 2.38 | 1.22 |
| 2009 | 1.98 | 2.5 | 1.71 |
| 2008 | 2.42 | 4.29 | 1.13 |
| 2007 | 2.88 | 4.9 | 1.31 |
| 2006 | 1.2 | 1.67 | 0.77 |
| 2005 | 1.07 | 1.43 | 0.74 |
| 2004 | 2.1 | 4.03 | 1.07 |