| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.42 | 1.65 | 1.21 |
| 2024 | 1.12 | 1.55 | 0.82 |
| 2023 | 0.96 | 1.21 | 0.73 |
| 2022 | 0.82 | 1.33 | 0.55 |
| 2021 | 0.98 | 1.35 | 0.82 |
| 2020 | 0.72 | 1.52 | 0.49 |
| 2019 | 0.63 | 1.06 | 0.49 |
| 2018 | 0.51 | 0.64 | 0.4 |
| 2017 | 0.76 | 0.93 | 0.6 |
| 2016 | 0.89 | 1.1 | 0.7 |
| 2015 | 1.07 | 1.83 | 0.62 |
| 2014 | 0.42 | 0.75 | 0.3 |
| 2013 | 0.34 | 0.44 | 0.3 |
| 2012 | 0.3 | 0.38 | 0.26 |
| 2011 | 0.44 | 0.59 | 0.29 |
| 2010 | 0.8 | 1.37 | 0.51 |
| 2009 | 0.88 | 1.46 | 0.37 |
| 2008 | 0.69 | 1.48 | 0.3 |
| 2007 | 1.34 | 1.96 | 0.68 |
| 2006 | 0.75 | 0.95 | 0.54 |
| 2005 | 0.78 | 1.08 | 0.59 |
| 2004 | 1.22 | 2.29 | 0.64 |