| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.02 | 1.47 | 0.69 |
| 2024 | 0.63 | 0.83 | 0.46 |
| 2023 | 0.71 | 0.94 | 0.59 |
| 2022 | 0.67 | 0.93 | 0.54 |
| 2021 | 0.96 | 1.3 | 0.81 |
| 2020 | 1.41 | 1.97 | 1.07 |
| 2019 | 1.37 | 1.72 | 1.16 |
| 2018 | 1.43 | 1.65 | 1.15 |
| 2017 | 1.57 | 2.03 | 1.25 |
| 2016 | 1.87 | 2.66 | 1.6 |
| 2015 | 2.32 | 3.67 | 1.61 |
| 2014 | 1.43 | 1.71 | 1.16 |
| 2013 | 1.78 | 2.45 | 1.26 |
| 2012 | 1.57 | 2.07 | 0.99 |
| 2011 | 2.37 | 3.49 | 1.74 |
| 2010 | 2.77 | 3.67 | 2.09 |
| 2009 | 2.04 | 2.68 | 1.49 |
| 2008 | 1.94 | 3.59 | 0.98 |
| 2007 | 2.68 | 3.82 | 1.7 |
| 2006 | 1.9 | 2.69 | 1.46 |
| 2005 | 1.68 | 2.04 | 1.14 |
| 2004 | 2.09 | 2.9 | 1.41 |