| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.35 | 1.41 | 1.25 |
| 2024 | 1.34 | 1.66 | 1.11 |
| 2023 | 1.55 | 1.78 | 1.33 |
| 2022 | 1.73 | 2.42 | 1.37 |
| 2021 | 2.21 | 2.65 | 1.9 |
| 2020 | 5.57 | 12.86 | 1.83 |
| 2019 | 2.63 | 4.96 | 1.33 |
| 2018 | 1.74 | 2.64 | 1.24 |
| 2017 | 3.22 | 4.28 | 2.48 |
| 2016 | 4.59 | 6.81 | 3.5 |
| 2015 | 7.35 | 11.75 | 4.55 |
| 2014 | 6.54 | 7.92 | 5.06 |
| 2013 | 5.8 | 8.59 | 4.07 |
| 2012 | 7.08 | 8.53 | 5.63 |
| 2011 | 6.77 | 9.01 | 4.96 |
| 2010 | 9.3 | 10.44 | 7.85 |
| 2009 | 10.37 | 11.65 | 8.36 |
| 2008 | 12.08 | 18.2 | 5.56 |
| 2007 | 20.78 | 37.91 | 10.95 |
| 2006 | 7.64 | 12.6 | 3.09 |
| 2005 | 2.86 | 3.86 | 1.38 |
| 2004 | 3.74 | 5.17 | 2.75 |