| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 4.62 | 5.08 | 4.03 |
| 2024 | 3.78 | 6.72 | 2.64 |
| 2023 | 3.19 | 4.76 | 2.48 |
| 2022 | 2.57 | 3.15 | 2.11 |
| 2021 | 2.46 | 3.4 | 1.77 |
| 2020 | 5.52 | 9.63 | 2.8 |
| 2019 | 3.22 | 5.62 | 2.52 |
| 2018 | 4.43 | 6.44 | 2.87 |
| 2017 | 6.87 | 10.31 | 5.27 |
| 2016 | 12.68 | 16.21 | 9.74 |
| 2015 | 15.64 | 30.22 | 9.97 |
| 2014 | 9.42 | 13.78 | 7.04 |
| 2013 | 8.69 | 10.55 | 7.33 |
| 2012 | 8.24 | 10.68 | 5.4 |
| 2011 | 7.87 | 9.48 | 5.68 |
| 2010 | 9.02 | 12.87 | 6.75 |
| 2009 | 9.57 | 13.14 | 6.5 |
| 2008 | 13.85 | 27.89 | 5.55 |
| 2007 | 10.02 | 16.55 | 4.34 |
| 2006 | 3.99 | 4.81 | 3.1 |
| 2005 | 3.01 | 4.28 | 1.63 |
| 2004 | 3.3 | 5.75 | 2.26 |