| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.27 | 1.51 | 1.13 |
| 2024 | 1.41 | 1.83 | 1.1 |
| 2023 | 1.82 | 2.85 | 1.58 |
| 2022 | 1.82 | 2.19 | 1.5 |
| 2021 | 2.02 | 2.56 | 1.78 |
| 2020 | 2.64 | 3.29 | 2.08 |
| 2019 | 3.36 | 4.51 | 2.25 |
| 2018 | 5.39 | 7.48 | 3.81 |
| 2017 | 4.85 | 6.63 | 4 |
| 2016 | 5.31 | 6.2 | 4.2 |
| 2015 | 7.03 | 10.01 | 4.9 |
| 2014 | 7.42 | 10.82 | 5.89 |
| 2013 | 10.82 | 13.44 | 7.47 |
| 2012 | 6.93 | 8.01 | 5.7 |
| 2011 | 10.31 | 13.3 | 7.79 |
| 2010 | 12.03 | 14.96 | 8.12 |
| 2009 | 11.26 | 13.82 | 9.58 |
| 2008 | 12.29 | 17.19 | 9.04 |
| 2007 | 9.12 | 15.22 | 2.89 |
| 2006 | 2.71 | 3.4 | 1.92 |
| 2005 | 2.29 | 2.91 | 1.8 |