| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.03 | 2.06 | 1.99 |
| 2024 | 1.91 | 2.47 | 1.45 |
| 2023 | 2.24 | 2.75 | 1.95 |
| 2022 | 1.83 | 2.99 | 1.37 |
| 2021 | 1.84 | 2.18 | 1.62 |
| 2020 | 2.64 | 3.59 | 2.08 |
| 2019 | 2.76 | 3.53 | 2.19 |
| 2018 | 2.68 | 3.6 | 1.87 |
| 2017 | 4.44 | 8.14 | 2.71 |
| 2016 | 7.03 | 8.77 | 5.36 |
| 2015 | 8.97 | 19.05 | 4.09 |
| 2014 | 3.92 | 5.2 | 3.03 |
| 2013 | 3.75 | 4.46 | 3.09 |
| 2012 | 4.15 | 6.13 | 2.73 |
| 2011 | 8.37 | 16.97 | 4.53 |
| 2010 | 11.76 | 16.37 | 8.95 |
| 2009 | 8.9 | 10.82 | 7.24 |
| 2008 | 11.11 | 21.53 | 4.7 |
| 2007 | 14.04 | 23.26 | 5.12 |