| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.09 | 2.3 | 1.92 |
| 2024 | 2.01 | 2.33 | 1.77 |
| 2023 | 2.61 | 3.49 | 2.1 |
| 2022 | 3.58 | 4.91 | 2.76 |
| 2021 | 4.78 | 5.85 | 3.4 |
| 2020 | 4.81 | 7.26 | 2.84 |
| 2019 | 3.4 | 3.96 | 2.94 |
| 2018 | 4.26 | 5.43 | 2.66 |
| 2017 | 3.89 | 5.32 | 3.02 |
| 2016 | 3.01 | 3.53 | 2.23 |
| 2015 | 2.43 | 3.58 | 1.71 |
| 2014 | 1.69 | 2.14 | 1.42 |
| 2013 | 2.01 | 2.55 | 1.67 |
| 2012 | 3.01 | 4.09 | 1.54 |
| 2011 | 4.81 | 6.88 | 3.63 |
| 2010 | 5.85 | 7.33 | 4.97 |
| 2009 | 3.84 | 5.61 | 2.34 |
| 2008 | 3.56 | 8.35 | 1.63 |
| 2007 | 6.16 | 10.36 | 3.27 |
| 2006 | 2.57 | 3.62 | 1.95 |
| 2005 | 1.87 | 2.22 | 1.38 |
| 2004 | 2.42 | 4.29 | 1.51 |