| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 4.55 | 7.55 | 3.6 |
| 2024 | 3.59 | 5.58 | 2.19 |
| 2023 | 4.31 | 5.51 | 3.45 |
| 2022 | 4.15 | 6.34 | 3.28 |
| 2021 | 4.98 | 5.6 | 4.24 |
| 2020 | 5.07 | 6.05 | 4.03 |
| 2019 | 5.4 | 7.85 | 4.52 |
| 2018 | 6.62 | 9.49 | 4.83 |
| 2017 | 9.65 | 10.85 | 8.01 |
| 2016 | 8.1 | 11.27 | 5.25 |
| 2015 | 9.97 | 12.93 | 5.75 |
| 2014 | 6.02 | 7.76 | 2.53 |
| 2013 | 3.29 | 4.05 | 2.66 |
| 2012 | 5.11 | 7.91 | 3.37 |
| 2011 | 9.6 | 12.21 | 5.94 |
| 2010 | 8.63 | 13.76 | 5.66 |
| 2009 | 7 | 12.62 | 1.7 |
| 2008 | 1.82 | 3.17 | 0.92 |
| 2007 | 2.34 | 3.08 | 1.48 |
| 2006 | 1.23 | 1.71 | 0.7 |
| 2005 | 0.6 | 0.84 | 0.36 |
| 2004 | 0.68 | 1.17 | 0.49 |