| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.97 | 2.21 | 1.7 |
| 2024 | 1.51 | 2.24 | 1.17 |
| 2023 | 3.23 | 5.33 | 1.81 |
| 2022 | 3.22 | 4.95 | 1.66 |
| 2021 | 2.16 | 3.5 | 1.34 |
| 2020 | 1.58 | 2.03 | 1.25 |
| 2019 | 1.86 | 2.5 | 1.23 |
| 2018 | 2.18 | 3.29 | 1.3 |
| 2017 | 3.81 | 4.71 | 3.14 |
| 2016 | 4.83 | 6.08 | 3.67 |
| 2015 | 5.71 | 10.27 | 3.07 |
| 2014 | 3 | 3.83 | 2.26 |
| 2013 | 2.18 | 2.69 | 1.85 |
| 2012 | 2.79 | 4.23 | 1.75 |
| 2011 | 6.5 | 10.84 | 3.21 |
| 2010 | 10.99 | 14.84 | 7.31 |
| 2009 | 8.71 | 12.06 | 5.45 |
| 2008 | 8.01 | 18.52 | 2.32 |
| 2007 | 13.01 | 25.25 | 2.29 |