| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2024 | 1.17 | 1.73 | 0.84 |
| 2023 | 1.22 | 1.57 | 0.87 |
| 2022 | 1.22 | 1.67 | 1.02 |
| 2021 | 1.06 | 1.91 | 0.6 |
| 2020 | 0.72 | 0.85 | 0.62 |
| 2019 | 0.91 | 1.09 | 0.75 |
| 2018 | 1.3 | 2.08 | 0.84 |
| 2017 | 1.42 | 1.82 | 1.06 |
| 2016 | 1.24 | 1.73 | 0.94 |
| 2015 | 1.3 | 1.98 | 0.92 |
| 2014 | 1.14 | 1.56 | 0.96 |
| 2013 | 2.04 | 3.36 | 1.33 |
| 2012 | 3.21 | 4.54 | 2.08 |
| 2011 | 5.22 | 6.73 | 3.09 |
| 2010 | 4.77 | 6.8 | 3.26 |
| 2009 | 5.34 | 7.31 | 2.8 |
| 2008 | 7 | 12.25 | 1.99 |
| 2007 | 10.03 | 14.57 | 3.6 |