| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.14 | 1.21 | 1.1 |
| 2024 | 1.25 | 1.57 | 1.07 |
| 2023 | 1.47 | 1.71 | 1.24 |
| 2022 | 1.16 | 1.57 | 0.94 |
| 2021 | 1.13 | 1.3 | 0.95 |
| 2020 | 1.29 | 1.63 | 1.15 |
| 2019 | 1.63 | 2.17 | 1.4 |
| 2018 | 1.77 | 2.24 | 1.35 |
| 2017 | 2.47 | 2.8 | 2.05 |
| 2016 | 2.82 | 3.73 | 2.09 |
| 2015 | 3.21 | 5.13 | 2.05 |
| 2014 | 2.06 | 2.93 | 1.56 |
| 2013 | 2.11 | 2.8 | 1.7 |
| 2012 | 1.66 | 2.13 | 1.37 |
| 2011 | 2.29 | 2.91 | 1.54 |
| 2010 | 2.82 | 3.48 | 2.08 |
| 2009 | 2.14 | 3.16 | 1.22 |
| 2008 | 1.88 | 2.88 | 1.03 |
| 2007 | 2.38 | 3.61 | 1.16 |
| 2006 | 1.1 | 1.21 | 0.96 |
| 2005 | 1.01 | 1.19 | 0.84 |