| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 4.25 | 6.84 | 2.78 |
| 2024 | 3.11 | 4.28 | 2.37 |
| 2023 | 3.15 | 4 | 2.13 |
| 2022 | 2.32 | 2.61 | 2.08 |
| 2021 | 2.51 | 3.01 | 2.13 |
| 2020 | 3.55 | 4.39 | 2.97 |
| 2019 | 5.37 | 8.09 | 3.84 |
| 2018 | 6.75 | 9.99 | 4.63 |
| 2017 | 11.94 | 14.7 | 7.35 |
| 2016 | 11.74 | 15.13 | 9.42 |
| 2015 | 19.84 | 27.75 | 12.22 |
| 2014 | 13.64 | 17.76 | 11.55 |
| 2013 | 14.51 | 21.63 | 9.61 |
| 2012 | 15.17 | 20.66 | 10.2 |
| 2011 | 15.56 | 19.01 | 11.08 |
| 2010 | 15.15 | 19.39 | 8.58 |
| 2009 | 9.11 | 11.65 | 6.65 |
| 2008 | 10.58 | 18.32 | 5.04 |
| 2007 | 14.1 | 22.03 | 6.8 |
| 2006 | 11.14 | 19.19 | 5.76 |