| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.12 | 2.36 | 1.84 |
| 2024 | 1.69 | 2.61 | 1.08 |
| 2023 | 1.61 | 2.18 | 1.05 |
| 2022 | 1.13 | 1.51 | 0.83 |
| 2021 | 1.81 | 2.39 | 1.37 |
| 2020 | 2.33 | 3.25 | 1.4 |
| 2019 | 0.88 | 1.36 | 0.52 |
| 2018 | 0.72 | 1.13 | 0.47 |
| 2017 | 0.89 | 1.02 | 0.77 |
| 2016 | 0.95 | 1.18 | 0.71 |
| 2015 | 1.05 | 1.68 | 0.66 |
| 2014 | 0.6 | 0.76 | 0.47 |
| 2013 | 0.44 | 0.6 | 0.33 |
| 2012 | 0.39 | 0.47 | 0.31 |
| 2011 | 0.56 | 0.76 | 0.35 |
| 2010 | 0.93 | 1.18 | 0.66 |
| 2009 | 0.73 | 1.08 | 0.25 |
| 2008 | 0.62 | 1.39 | 0.22 |
| 2007 | 1.25 | 1.62 | 0.8 |
| 2006 | 0.85 | 1.03 | 0.69 |
| 2005 | 0.7 | 0.94 | 0.4 |
| 2004 | 0.76 | 1.35 | 0.54 |