| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2024 | 2.39 | 2.83 | 1.99 |
| 2023 | 1.84 | 2.04 | 1.59 |
| 2022 | 1.69 | 1.87 | 1.51 |
| 2021 | 2 | 2.28 | 1.76 |
| 2020 | 2.15 | 2.59 | 1.98 |
| 2019 | 2.7 | 2.98 | 2.43 |
| 2018 | 3.09 | 4.29 | 2.62 |
| 2017 | 3.04 | 3.6 | 2.53 |
| 2016 | 2.4 | 2.64 | 2.17 |
| 2015 | 2.72 | 3.25 | 2.18 |
| 2014 | 2.17 | 2.82 | 2.04 |
| 2013 | 2.62 | 3.06 | 2.24 |
| 2012 | 2.97 | 3.49 | 2.57 |
| 2011 | 3.77 | 4.41 | 3.21 |
| 2010 | 4.74 | 6.11 | 3.92 |
| 2009 | 5.17 | 6.3 | 3.8 |
| 2008 | 6.6 | 11.96 | 3.83 |
| 2007 | 10.95 | 13.21 | 9.23 |