| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.36 | 1.49 | 1.22 |
| 2024 | 1.4 | 1.62 | 1.07 |
| 2023 | 1.51 | 1.73 | 1.36 |
| 2022 | 1.39 | 2.16 | 1.15 |
| 2021 | 1.33 | 1.78 | 1.15 |
| 2020 | 1.46 | 1.71 | 1.3 |
| 2019 | 1.38 | 1.68 | 1.02 |
| 2018 | 1.2 | 1.4 | 0.97 |
| 2017 | 1.62 | 2.01 | 1.28 |
| 2016 | 2.03 | 2.57 | 1.83 |
| 2015 | 3.06 | 5.18 | 2.13 |
| 2014 | 2.45 | 2.85 | 1.68 |
| 2013 | 1.71 | 2.11 | 1.38 |
| 2012 | 1.9 | 2.28 | 1.29 |
| 2011 | 2.16 | 2.66 | 1.73 |
| 2010 | 2.9 | 3.56 | 2.2 |
| 2009 | 2.55 | 3.79 | 1.53 |
| 2008 | 2.5 | 5.32 | 1.08 |
| 2007 | 3.73 | 5.06 | 1.85 |
| 2006 | 1.79 | 2.16 | 1.51 |
| 2005 | 1.77 | 2.33 | 1.26 |
| 2004 | 2.09 | 3.84 | 1.37 |