| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 6.82 | 7.59 | 6.3 |
| 2024 | 5.88 | 7.87 | 4.81 |
| 2023 | 7.5 | 8.89 | 5.95 |
| 2022 | 9.13 | 13.96 | 6.11 |
| 2021 | 14.54 | 20.83 | 10.68 |
| 2020 | 9.99 | 15.73 | 5.25 |
| 2019 | 4.81 | 6.21 | 2.9 |
| 2018 | 3.25 | 4.19 | 2.5 |
| 2017 | 5.31 | 9.41 | 3.73 |
| 2016 | 8.53 | 10.48 | 6.06 |
| 2015 | 7.75 | 16.54 | 3.48 |
| 2014 | 3.72 | 10.93 | 1.15 |
| 2013 | 1.54 | 2.07 | 1.18 |
| 2012 | 2.36 | 3.45 | 1.64 |
| 2011 | 3.08 | 4.05 | 2.24 |
| 2010 | 4.68 | 12.73 | 2.93 |
| 2009 | 6.88 | 12.13 | 2.44 |
| 2008 | 4.86 | 10.37 | 1.77 |
| 2007 | 8.04 | 10.3 | 2.15 |
| 2006 | 1.39 | 2.15 | 0.86 |
| 2005 | 0.9 | 1.13 | 0.6 |
| 2004 | 1.63 | 3.54 | 1.05 |