| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.28 | 2.02 | 0.9 |
| 2024 | 0.92 | 1.83 | 0.6 |
| 2023 | 1 | 1.65 | 0.61 |
| 2022 | 0.74 | 0.84 | 0.59 |
| 2021 | 0.74 | 1.01 | 0.6 |
| 2020 | 1.44 | 2.44 | 0.7 |
| 2019 | 0.82 | 1.06 | 0.7 |
| 2018 | 0.95 | 1.36 | 0.71 |
| 2017 | 1.75 | 2.75 | 1.23 |
| 2016 | 2.02 | 2.46 | 1.66 |
| 2015 | 2.79 | 3.87 | 1.91 |
| 2014 | 1.49 | 2.37 | 1.1 |
| 2013 | 1.36 | 1.8 | 1.13 |
| 2012 | 1.4 | 1.7 | 1.14 |
| 2011 | 2.04 | 2.97 | 1.18 |
| 2010 | 2.08 | 2.97 | 1.43 |
| 2009 | 1.89 | 2.48 | 1.05 |
| 2008 | 1.93 | 4.15 | 0.84 |
| 2007 | 2.84 | 4.07 | 1.09 |
| 2006 | 0.69 | 1.11 | 0.44 |
| 2005 | 0.56 | 0.73 | 0.45 |
| 2004 | 0.96 | 2.07 | 0.48 |