| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.2 | 2.63 | 1.71 |
| 2024 | 1.48 | 2.25 | 0.86 |
| 2023 | 1.34 | 1.7 | 1.09 |
| 2022 | 1.69 | 2.19 | 1.25 |
| 2021 | 1.32 | 2.4 | 0.82 |
| 2020 | 1.01 | 1.58 | 0.83 |
| 2019 | 0.98 | 1.4 | 0.8 |
| 2018 | 1.59 | 2.5 | 0.83 |
| 2017 | 2.09 | 2.69 | 1.63 |
| 2016 | 2.68 | 4.49 | 2.15 |
| 2015 | 3.94 | 6.76 | 2.31 |
| 2014 | 2.5 | 3.2 | 1.89 |
| 2013 | 1.72 | 2.61 | 0.97 |
| 2012 | 1.14 | 1.6 | 0.82 |
| 2011 | 2.81 | 4.11 | 1.13 |
| 2010 | 4.27 | 5.98 | 2.97 |
| 2009 | 3.31 | 5.32 | 2.01 |
| 2008 | 5.62 | 15.66 | 1.12 |
| 2007 | 8.43 | 15.04 | 4.36 |
| 2006 | 3.56 | 5.58 | 1.83 |
| 2005 | 1.7 | 2.37 | 1.09 |