| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.89 | 2.23 | 1.67 |
| 2024 | 1.77 | 2.13 | 1.45 |
| 2023 | 2.5 | 3.33 | 1.92 |
| 2022 | 2.7 | 4.02 | 1.93 |
| 2021 | 2.35 | 3.59 | 1.78 |
| 2020 | 3.04 | 3.89 | 2.58 |
| 2019 | 3.43 | 6.2 | 1.69 |
| 2018 | 2.13 | 2.81 | 1.65 |
| 2017 | 4.8 | 6.82 | 2.58 |
| 2016 | 5.46 | 7.01 | 4.02 |
| 2015 | 5.76 | 7.69 | 4.51 |
| 2014 | 3.99 | 6.15 | 2.73 |
| 2013 | 2.64 | 3.1 | 2.09 |
| 2012 | 4.52 | 7.29 | 1.76 |
| 2011 | 7.04 | 9.42 | 5.08 |
| 2010 | 5.41 | 10.82 | 3.2 |
| 2009 | 3.1 | 4.31 | 1.75 |
| 2008 | 2.85 | 5.34 | 1.12 |
| 2007 | 4.24 | 5.82 | 3.27 |