| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.54 | 3.02 | 2.36 |
| 2024 | 2.55 | 3.62 | 2.06 |
| 2023 | 2.55 | 3.76 | 1.9 |
| 2022 | 2.07 | 2.5 | 1.69 |
| 2021 | 2.25 | 2.71 | 1.81 |
| 2020 | 3.34 | 4.3 | 2.51 |
| 2019 | 3.23 | 4.27 | 2.39 |
| 2018 | 3.74 | 5.13 | 2.52 |
| 2017 | 6.14 | 8.16 | 4.57 |
| 2016 | 7.88 | 10.14 | 5.37 |
| 2015 | 8.6 | 15.6 | 5.2 |
| 2014 | 7.01 | 8.71 | 5.71 |
| 2013 | 7.38 | 9.27 | 5.62 |
| 2012 | 7.86 | 9.85 | 6.07 |
| 2011 | 17.81 | 29.02 | 8.15 |
| 2010 | 17.37 | 27.19 | 10.7 |
| 2009 | 8.42 | 14.03 | 2.69 |
| 2008 | 3.82 | 7.03 | 1.77 |
| 2007 | 4.15 | 6.26 | 1.47 |
| 2006 | 1.38 | 2.01 | 0.82 |
| 2005 | 1.06 | 1.32 | 0.7 |
| 2004 | 1.46 | 2.36 | 0.88 |